Harvey was the youngest of three boys born to Ber "Boris" and Ella Skikne, a Jewish family in the town of Joniškis, Lithuania. At the age of five he emigrated with his family to South Africa where he took on the English name of Harry.

He grew up in Johannesburg, and was in his teens when he served with the entertainment unit of the South African Army during World War II. After moving to London, England, he enrolled in the Royal Academy of Dramatic Art where he became known as Larry.

After learning his craft at RADA, he began to perform on stage and film, where he adopted the stage name "Laurence Harvey", taken either from the shop name Harvey Nichols or from Harvey's Bristol Cream.

He made his cinema debut in the British film House of Darkness (1948) but didn't really establish himself in British cinema until 1954, when he appeared with Rex Harrison and George Sanders in King Richard and the Crusaders (1954) and as Romeo in Renato Castellani's adaptation of William Shakespeare's Romeo and Juliet, narrated by John Gielgud.

This enabled him to break out of the "ghetto" of British films and get his first experience of Hollywood. He was cast as the writer Christopher Isherwood in I Am A Camera (1955), opposite Julie Harris as Sally Bowles. (The same book by Isherwood was later adapted into the musical play Cabaret, whose film version starred Michael York and Liza Minelli).

He also appeared on American TV and on Broadway, making his Broadway debut in 1955 in the play Island of Goats, a flop which closed after one week, though his performance won Harvey a 1956 Theatre World Award.

Harvey appeared twice more on Broadway, in 1957 with Julie Harris, Pamela Brown, and Colleen Dewhurst in William Wycherley's The Country Wife, and as Shakespeare's Henry V in 1959, as part of the Old Vic company, which featured a young Judi Dench as Katherine, the Daughter of King of France.

In John Miller's biography of Dame Judi, With A Crack In Her Voice, she talked of being bewildered at how Harvey never actually looked at her during his speeches, and the book also quotes Joss Ackland as saying that Americans seemed to think Harvey was some sort of great actor, which his fellow actors certainly didn't.

Harvey was regularly dismissed by critics and disliked by fellow workers in the British theatre. In his posthumously published autobiography Knight Errant, Robert Stephens described him as "an appalling man and, even more unforgivably, an appalling actor."