Isserlis was born on 19 December 1958 in London into a musical family. His grandfather, who was a Russian Jew, was one of 12 musicians allowed to leave Russia in the 1920s to promote Russian culture, but he never returned. His mother was a piano teacher, and his father was a keen amateur musician. His sister Annette is a viola player, and his other sister Rachel is a violinist. He says that playing music, playing together, was part of his early family life. He went to the City of London School. He left school at the age of 14 and then moved to Scotland where he studied under the tutelage of Jane Cowan. He is a longtime Beatles fan, and his own distinctive hairstyle, a mop of thick curly, hair, was inspired by the Beatles. He is an acquaintance of Paul McCartney. His family was supportive of his early music career, even when he was not earning that much money.

He wife Pauline, a former flute player, died in June 2010. Their son, Gabriel, is currently studying to be a movie Director in the Rochester Institute of Technology //en.wikipedia.org/wiki/Rochester_Institute_of_Technology in America.

Isserlis plays both as soloist and chamber musician and has revived many neglected works.He has also organized a number of festivals with long-term collaborators such as Joshua Bell, Stephen Hough, Mikhail Pletnev, Andras Schiff, Denes Varjon, and Tabea Zimmermann. Many new works have been written for him by composers such as John Tavener, Thomas Ades, Wolfgang Rihm, Carl Vine, and Douglas Weiland.

He was awarded a CBE in 1998, and collected his award with his father, as his mother died earlier that week. He was awarded the Schumann Prize 2000 by the city of Zwickau.He plays the De Munck Stradivarius, on loan from The Nippon Music Foundation. He also part-owns a Montagnana cello from 1740 and a Guadagnini cello of 1745, which he played exclusively from 1979 to 1998 and part-owns with David Waterman, cellist of the Endellion Quartet.

He is also the author of two books for children on the lives of famous composers: the first is Why Beethoven Threw the Stew (Faber & Faber, 2001), and the second Why Handel Waggled His Wig (Faber & Faber, 2006). He has also written 3 stories that have been set to music by Anne Dudley: "Little Red Violin," Goldipegs and the Three Cellos, and Cindercella (Published by Universal Edition, Vienna). He has also made several additions for Faber Music and sheetmusicnow.com.

Isserlis is artistic director of the International Musicians Seminar, Prussia Cove in West Cornwall, where he both performs and teaches.

In 2007, Isserlis' recording of the Bach Cello Suites was released and won a "Gramophone" award.

Isserlis made his debut directing from the cello in February 2008, with the Irish Chamber Orchestra at the National Concert Hall in Dublin.