Born in Romford, Essex, he was the only child of working class parents. He spent the first five years of his life in a rented flat above a shop in Essex, before his family moved to their own house in Billericay, Essex.

His father was a former Royal Naval Commando who won the Distinguished Service Medal in World War Two. After the war, he worked as a lorry driver, market trader and greengrocer. His mother was a school dinner lady. Parsons attended a grammar school but dropped out when he was 16 years old and worked in a series of low-paid, unskilled menial jobs. Then he got a job with a city insurance company as a computer operator where his free time allowed him to develop his literary skills ... publishing an underground paper called the Scandal Sheet.

Parsons married fellow NME journalist Julie Burchill ... they had both answered the same advert in the paper requesting "hip, young gunslingers" to apply as new writers. He and Burchill collaborated on a book in 1979 ... The Boy Looked at Johnny. Together they had a son, Bobby Kennedy Parsons. After the collapse of this marriage in 1984, Parsons became a single parent caring for their 4-year-old son. The experience of being a young man caring for a small child was to later influence his best-selling novel, Man and Boy. Parsons' father died of cancer in 1987 and his mother died of cancer in 1999, just weeks before the publication of Man and Boy. The book is dedicated to Parsons' mother.

In 1992, Parsons married his Japanese wife, Yuriko. They have one daughter, Jasmine. He lives with his wife and daughter in London.

In 1974 he began work in Gordon's Gin Distillery on City Road, London, where he developed an acute gin allergy and wrote his first novel, The Kids, published by New English Library in 1976. Parsons later said that he had imagined that if he could publish a book then he would be able to make a living as a professional writer. The £700 he made from the Kids did not get him out of Gordon's gin factory. However, when the weekly music magazine New Musical Express advertised for new writers in the summer of 1976 Parsons submitted his novel to the editor, Nick Logan, and was rewarded with a staff writer job. For the next three years he wrote about new music. He wrote the first cover story on The Clash, and features of The Sex Pistols, Blondie, Talking Heads, Ramones, David Bowie, Bruce Springsteen, New York Dolls, Buzzcocks, Led Zeppelin and many more.

For most of the eighties Parsons struggled to make a living as a freelance writer. After a long spell in the doldrums, his career only started to recover in the nineties. Parsons became a regular on the live BBC panel show panel show, Late Review. He made a series of controversial authored documentaries for Channel 4. When Piers Morgan became editor of the Daily Mirror, Parsons was poached from The Daily Telegraph as a columnist.

In 1990 he wrote Bare, an authorised biography of pop-star George Michael. Despite the absence of a written contract with the singer, proceeds from the book were split equally between the two men. However, they fell out in 1999 after an interview Michael had given to Parsons was published in the Daily Mirror.

In 1993 he presented a film for the British television documentary series Without Walls, focusing on the controversy surrounding the 1971 film A Clockwork Orange. Director Stanley Kubrick and distributor Warner Brothers unsuccessfully sued broadcaster Channel Four in an attempt to prevent clips from the film being shown on television. In the programme, Parsons is seen taking a cross-channel ferry from England to France to watch the film, which at the time was still embargoed in Britain due to a self-imposed ban by the director.

Though it sold respectably on publication, the 1999 novel Man and Boy was a word-of-mouth success, and only reached number one in The Sunday Times best-seller list one year after publication. Despite the publication of a series of novels, Man and Boy remains his best-selling book, being published in 39 languages, most recently Chinese for its publication in the People's Republic of China (January 2009). Man and Boy won the British Book Awards' Book of the Year Prize in 2001.

In 2009 Parsons signed a three-book contract with HarperCollins for two further novels and a non-fiction book called, Fear of Fake Breasts. Parsons also writes a monthly column for GQ magazine and a weekly column for the Daily Mirror.