Han's first essay, Unhappy Days (???????), was published when he was attending junior middle school. He was admitted to Shanghai's Song Jiang No. 2 High School (???????) based on his sporting achievements. During his first year of high school (1999), Han won first prize in China's New Concept Writing Competition with his essay, Seeing Ourselves in a Cup (????), on the Chinese national character. Failing seven subjects at the year-end examination, Han was retained for a year in school. This incident was reported in the media and ignited a heated debate on China's "quality education" (????) policy, whether holistic or specialised learning should be implemented in schools, and other educational issues. Following another seven subject failure in the senior middle school second year examinations, Han quit school.

After dropping out of school, Han worked on a series of essays – One Degree Below Freezing (????), Press Release 2003 (?? 2003), And I Drift (???????), and Miscellaneous Essays (???). His essays were accepted into various publications. Han's first novel, Triple Door (???), on life as a third-year junior school student in Shanghai, raised his prominence in China outside Shanghai. With over two million copies printed, this novel is China's bestselling literary work in the last 20 years. Other novels – Like a Speeding Youth (??????), Riot in Chang'an City (???), A Fortress (????), Glory Days (???), His Kingdom (???) were also published during this time.

Fueled by his love of racing, Han became a professional rally driver and wrote less frequently. However, he continued to blog on current affairs, with some articles attracting a large number of readers and sparking intense debates. Han's blog has registered well over 300 million hits, the largest online following of a personal blog in China.

In February 2005, a Hollywood movie was planned with the script to be based on Chinese writer Xie Hang's novel, Dysmenorrhoea (??), and filming to take place in a northern Chinese city. As Han's image suited him to play the male lead role, the Chinese partner company recommended him for the role to the American producers. When media outlets asked Han for his views on this matter, he replied, "I have yet to receive this invitation, but basically I would reject it." He explained, "It doesn't matter that this is a Hollywood movie, as my decision would depend on who's playing the female lead." On hearing that the script was about the forbidden love between a boy and his female teacher, Han laughed and rejected the role, saying, "This makes it even more difficult for me, I will not play such a role."

Han is also involved in music production. His debut album, R-18 (???, restricted to 18 and above), was released in September 2006, with all lyrics self-composed.

The Han-Bai controversy

On 2 March 2006, Chinese literary critic and bookseller Bai Ye (??) published a blog post entitled, Status and Future of the Post-80 Generation (”80?“?????), criticizing the works of writers born in the 1980–1989 period. As this was the first decade during which China's one-child policy was in effect, most of these writers were only children. Han responded critically with his online article The "Literary Circle" Is Bullshit, Don't Act Pretentious (????? ?????). This exchange escalated into the "Han-Bai controversy", with both sides arguing on issues such as the post-80 classification, whether the works of post-80s qualified as literature and whether post-80 writers should be considered real writers.

On 4 March 2006, Bai published an online article entitled My Declaration – a Reply to Han Han (???? – ????), stating that Han's articles in this exchange had crossed the boundaries of literary debate into the realm of humiliation and personal attack. Subsequently, writer Lu Tianming (???), his director son Lu Chuan (??), and musician Gao Xiaosong (???), entered the debate, which became the focus of the online community for a time. Han debated with the above personalities on his blog. The debate finally concluded with Bai, Lu Tianming, Lu Chuan, and Gao shutting down their personal blogs.

Other controversies

Questioning the value of modern Chinese free verse, Han posted a blog article on 26 September 2006 entitled Why do modern Chinese poetry and poets still exist? (????????????). In this and other related articles, he parodied modern Chinese poets including the late Xu Zhimo (???) and the late Hai Zi (??), igniting a controversy involving poets such as the Lower Body Poet Shen Haobo, Yang Li (??), Yi Sha (??), and Dong Li (??).On 10 April 2007, Han criticised rock singer Zheng Jun's (??) capriciousness in a blog post entitled Some Recent Arrangements (???????), igniting a controversy between the two. In 2006, Zheng condemned the Super Girl singing competition (????) as being "unbearably disgusting", but participated in the judging for a similar competition Super Boy (????) in 2007.

On 19 April 2009, Han launched his online bookstore, Han Han's Bookstore, on the Taobao online shopping marketplace (???). The bookstore site stated that it would sell only Han's original autographed books. As the number of sales transactions on Han Han's Bookstore was unusually large, the online system erroneously classified these as false transactions and attempts at credit fraud, leading Taobao to investigate the issue.

On 1 May 2009, Han posted an article on his blog entitled Request for articles, recruitment, article fees and article submission email address for a new magazine. The post mentioned that Han would be setting up a magazine, informing the email addresses for article submission, response to recruitment ads, and advertising offers, but without revealing the magazine title to prevent illegal copying. Notably, the blog post also mentioned that the writer of the selected cover story, if the story had not been previously published, would stand to get up to RMB 2,000 per 1,000 characters in article fees. This would be 10 to 40 times of the standard rate in China's publishing industry, and 2 to 4 times higher than what China's top magazine would pay China's top writer for an article. Writers of previously unpublished non-cover story articles in the magazine would be paid RMB 1,000 per 1,000 characters, 10 to 20 times higher than standard rates in the publishing industry. As for previously-published articles or selected extracts from articles, the rate would be RMB 500 per 1,000 characters, which would be about 15 times the standard rates. Contributors of photographs would be paid up to RMB 5,000 per photograph.

Han also invited article submissions for a "braindead" (??) column, deliberately publishing articles that the magazine disagreed with or were not up to standards. The rate for such articles would be RMB 250 per 1,000 characters. 250 () is a Chinese slang with the same meaning of "You idiot". Han gave the rationale for including this column:

Within five days of putting up the blog post, Han received over 10,000 article submissions from across China, and also a few thousand résumés. Interestingly, there were several articles of the types which Han had expressly forbidden from submission, such as cut and paste jobs, pornographic literature and dissertations. Han expressed his exasperation with these and declared that such articles would not be published.

Han's setup of his magazine received widespread attention, with editors proclaiming that the higher fees enabled the writing profession to regain a measure of financial independence and dignity One journalist even commented that Han had completed his transformation from a rebellious youth into a full-fledged intellectual.

Due to certain publishing and circulation restrictions in China, Han's magazine, which was originally planned for publication in August 2009, remained unpublished as of 20 September 2009. Despite this, Han promised not to disappoint his readers and expressed hope that the magazine could be published sometime around October 2009.As of February 2010 the magazine has not been published reportedly because of an article that details the blacklisting of actors.On July 6 2010, his magazine Party (???? is finally published.According to the publisher, the magazine became the most popular book on Amazon.cn less than 10 hours after pre-selling.

After Han turned professional as a rally driver, there were rumours that he had encountered financial difficulties. Han himself admitted that writers and race car drivers in China earned less compared to those in other professions. Furthermore, his only income source was from book royalties as he was not involved in other revenue generating activities. However, he continued to race as it gave him a sense of achievement. Winning prizes also enabled him to prove to himself that he was an all-rounded learner. As Han stated in a media interview in 2007:

The following highlights some of Han's achievements in his racing career:

• 2003: Raced for Beijing Extreme Speed Racing Team (??????) in the China Rally. Achieved 6th in the Shanghai race, 8th in the Changchun race and 6th in the Beijing race, all in the Group N category.
• 2004: Group N 7th position for the Shanghai race, 4th position for the all-China race.
• 2004 June: Joined Yunnan Red River Racing Team (??????).
• 2004: Took 1st position in the Formula BMW Asia Qualifying Race (??????????). Received scholarship money of USD 50,000.
• Entered the annual Formula BMW race, achieved 7th in the Bahrain race and 1st in the Rookie Cup.
• 8th in the Malaysia Race, 2nd in the Rookie Cup.
• 7th in the Shanghai race, 2nd in the Rookie Cup.
• 6th in the Japan race, 1st in the Rookie Cup.
• 2005: Joined Shanghai Volkswagen 333 Racing Team (????333??).
• 2005: Participated in the China Rally 1.6L Category. Achieved 4th in the Shanghai race, 4th in the Guizhou race, 4th in the Liupanshui race, and 4th in the Kunming race.
• 2005: Participated in the China Circuit Championship Production Car 1600cc Category (????????? ?????1600cc?). Took 1st position in the Zhuhai race, 2nd position in the Shanghai race, 3rd position in the Beijing race and 1st position in the Shaoguan race. Won overall 2nd prize for 2005.
• 2006: Raced for Shanghai Volkswagen 333 Racing Team. Won 3rd prize in the Shanghai race of the China Circuit Championship 1600cc Category, and 2nd prize in the China Rally.
• 2007: Raced for Shanghai Volkswagen 333 Racing Team, obtained 1st prize in the China Circuit Championship 1600cc Category.

In September 2009, Han travelled to Australia to participate in the World Rally Championship (WRC). Following this, he wrote a blog post entitled Report on supervision and guidance work in preparation for the WRC in Australia (?????????????????????), using irony to express dissatisfaction with China's standards of race management, economic conditions, political consciousness of the population, etc. in comparison with Australia.