Ron Larson was born in Fort Lewis, Washington, the second of four children of Mederith John Larson and Harriet Eleanor Larson. Mederith Larson was an officer in the 321st Engineer Battalion of the United States Army. He served in active duty during World War II, where he was awarded a Bronze Star Medal and a Purple Heart, and the Korean War, where he was awarded an Oak Leaf Cluster and a Silver Star. During the years that Ron was growing up, his father was stationed in several military bases, including Chitose, Hokkaido, Japan and Schofield Barracks, Hawaii. While in Chistose, Ron attended a small DoDDS school, where he was one of only three students in the sixth grade. When Mederith Larson retired from the Army in 1957, he moved with his family to Vancouver, Washington, where he lived until he died in 2005. Harriet Larson died in the fall of 2009.

Larson spent his first two years of high school at Leilehua High School in Wahiawa, Hawaii. In 1957, when his family moved to Vancouver, Washington, Larson enrolled in Battle Ground High School, where he graduated in 1959. On October 29, 1960, at the age of 18, he married Deanna Sue Gilbert, also of Vancouver, Washington. Deanna Gilbert was the second child Herbert and Dorothy Gilbert. Ron and Deanna Larson have two children, Timothy Roland Larson and Jill Deanna Larson Im, and five living grandchildren. Their first grandchild, Timothy Roland Larson II, died at birth on summer solstice, June 21, 1983.

Larson is the third generation of Norwegian and Swedish immigrants who left Scandinavia to homestead in Minnesota in the late 1800s. The surnames and immigration dates of his great-grandparents are Bangen (1866, Norway), Berg (1867, Norway), Larson (1868, Norway), and Watterburg (1879, Sweden).

From 1959 until 1962, Ron and Deanna Larson started and operated a small business, called Larson's Custom Quilting. In 1962, they sold the business and Ron began attending Clark College in Vancouver, Washington. In 1964, he obtained his associate's degree from Clark. Upon graduation from Clark College, Larson was awarded a scholarship from the Alcoa Foundation, which he used to attend Lewis & Clark College in Portland, Oregon. He graduated, with honors, from Lewis & Clark in 1966. During the four years from 1962 through 1966, Ron worked full-time, first at a restaurant and then at a grocery store, in Vancouver and Deanna worked full-time as a secretary at Roberts Motor Company in Portland, Oregon.

From 1966 to 1970, Larson attended graduate school at the University of Colorado at Boulder. He received his master's degree in 1968 and his Ph.D. in mathematics in 1970. While at the University of Colorado, Larson was the recipient of an NDEA scholarship and an NSF fellowship. He also served as a teaching assistant. His Ph.D. dissertation "On the Lattice of Topologies" was written under Wolfgang J. Thron . Larson's Ph.D. lineage, as listed by the University of North Dakota, traces back through George David Birkhoff, Joseph Louis Lagrange, Leonhard Euler, and Gottfried Wilhelm Leibniz, the co-developer of calculus.

In 1970, Larson accepted a position of assistant professor at The Pennsylvania State University The Behrend College in Erie, Pennsylvania. At the time, Behrend College was a 2-year branch campus of the university. In 1971, the Board of Trustees of the University met with the Behrend Advisory Board to announce Behrend College would become the first location outside University Park with the authority to develop baccalaureate program and confer degrees locally. During his first several years at the college, Larson was instrumental in developing a mathematics major at the college. He served as a member of the University Faculty Senate and also as Behrend College's representative on the University Faculty Council. Larson was promoted to associate professor in 1976 and professor in 1983. Early in his career at Penn State, Larson started writing manuscripts for textbooks. He completed and submitted three manuscripts for calculus texts in 1973, 1974, and 1975 ... only to be rejected by several publishers. Finally, in 1976 he and his co-author, Robert P. Hostetler, obtained a contract from D. C. Heath and Company. The first edition of their calculus book was published in December, 1978. "Calculus" by Larson and Bruce Edwards is now in its ninth edition and is used worldwide.

During the academic year of 1983–84, Larson served as the acting division head for the Division of Science at Penn State Erie.

In 1998 Larson was given the Distinguished Alumnus Award from Lewis and Clark College, Portland, Oregon.

Counting different editions, he has written over 400 titles. They are used by several million students each year in the United States, as well as by students in other countries. Larson's books have received many awards – for pedagogy, innovation, and design. One of these awards was for developing the first completely interactive calculus textbook on-line. The work on this text was spearheaded by Larson’s son, Timothy Larson. The on-line text, titled Interactive Calculus was posted in 1995. Another award was for innovation in page design. Beginning in 1990, Larson has written all of his mathematics texts to design, so that concepts and examples never break from page to page. The eighth edition of Calculus won the 2005 Benny Award for the best cover in all categories of printing. The middle school series, Big Ideas Math, won the Texty Award in 2010 for excellence in secondary mathematics textbook publishing.

Up until 1995, most of Larson's books were published by D. C. Heath, which was owned by Raytheon. In 1995, Raytheon sold D. C. Heath to Houghton Miffin. By 1999, Larson's titles had become a major component of Houghton Mifflin's publications. In that year, he was listed in the company's annual report as one of Houghton Mifflin's major authors. In 2008, the College Division of Houghton Mifflin was sold to Cengage Learning.

Larson's textbooks have been translated into Spanish, Portuguese, and Chinese.

In 1984, Larson formed a small company that he called Larson Texts, starting with four employees in an old cottage on the campus of Behrend College. The cottage had been part of the original estate of Ernst Behrend, founder of Hamermill Paper Company.

This company grew through a sequence of larger offices. In 1992, Larson gave up his sole proprietorship of the company to form a corporation called Larson Texts, Inc.. In the same year the company purchased Typographics, a small typesetting firm in Erie, Pennsylvania. Typographics came with a group of employees who were experienced in design, graphic arts, and composition.

In 2000, the company bought and renovated the former Belle Valley School into a office building. It has over 50 employees, who work in design, composition, and research ... all connected with the development and production of Larson's textbooks. In 2000, it was listed in the Top Ten Best Places to Work in Pennsylvania for medium sized companies.

In 1992, Larson Texts formed a software division called Meridian Creative Group, later renamed as Larson Learning. The division developed and sold tutorial mathematics software for grades K through 8. In 2005, Larson Learning was sold to Houghton Mifflin for $7 million.

1. Larson, Ron; Robyn Silbey (1998). "Larson's Middle School Math, Grades 6, 7, and 8". Larson Learning
2. Larson, Ron (2000). "Larson's Intermediate Math, Grades 3, 4, 5, and 6". Larson Learning
3. Larson, Ron (2002). "Larson's Elementary Math, Grades Kindergarten, 1, and 2". Larson Learning

During his first few years as an assistant professor at Penn State Erie, Larson continued to do research in the area of his dissertation. His research resulted in the publication of several articles, mostly dealing with the lattice of topologies. By the mid-1970s, however, he switched his writing efforts to textbooks.

1. Larson, R. E., R. P. Hostetler and B. A. Edwards (June 1994, July 1994). "CD-ROM Textbook and Calculus". FOCUS: Mathematics Association of America.

Larson is an active member of the three American mathematics teaching organizations: the National Council of Teachers of Mathematics, the American Mathematical Association of Two-Year Colleges, and the Mathematical Association of America. He is a frequent speaker at each of these organizations' state and national conferences.

Ron and Deanna Larson have been active in philanthropy at Penn State University. They are members of the Mount Nittany Society, which recognizes individuals who have given over $250,000 to the university.

Until 2008, all of Larson's textbooks were published by D. C. Heath, McGraw Hill, Houghton Mifflin, Prentice Hall, and McDougal Littell. In 2008, Larson was unable to find a publisher for a new series for middle school to follow the 2006 "Focal Point" recommendations of the National Council of Teachers of Mathematics.. He therefore started a new company to publish the books, Big Ideas Learning, LLC.

According to his acceptance speech for the Distinguished Alumnus Award in 1998, Ron's interest in writing mathematics textbooks started the summer after his sophomore year in college. "In my sophomore year I decided to switch to math. I wasn't prepared for it. I had forgotten my high school algebra and trig, and I had to spend my sophomore year taking those courses over again. After I was accepted to Lewis & Clark, I made an appointment to talk with the math department chair, Elvy Fredrickson. That was in June 1964. I asked Elvy if she would let me squeeze four years of math into my junior and senior years at Lewis & Clark. To imagine her thoughts, you have to remember that I had not even taken a course in freshman calculus. I didn't then know what Elvy was thinking. I only knew what she said and what she did. She went to a bookshelf in her office in the old math building, scanned the titles, took down a calculus text, handed it to me, and said, 'Study this book during the summer. The week before classes start in the fall, I will give you a test. If you pass, I will let you take your sophomore and junior mathematics courses concurrently. By the time you reach your senior year, you will be on track.' Years later, Elvy told me that she had no idea I would actually do it. But, I had no idea that she had no idea—and so I took her up on her offer. I read the calculus book, passed the test, and started taking third-semester calculus and linear algebra in the fall of 1964."