Kapoor attended Don Bosco High School in Matunga, Mumbai. He met English actress Jennifer Kendal in Calcutta in 1956 while both were working for their respective theatre groups. Shashi was both assistant stage manager as well as an actor for his father's theatre group, Prithvi Theatre. Geoffrey Kendal's Shakespearean group was also present at the same time in Calcutta and Jennifer was Geoffrey's daughter. After their subsequent meeting, the couple fell in love and after facing initial opposition from the Kendals and support from sister-in-law Geeta Bali, they got married in July 1958. They acted in a number of films together, most notably in Merchant Ivory productions. They had three children: Kunal Kapoor, Karan Kapoor and Sanjana Kapoor. Jennifer and Shashi established Prithvi Theatre on 5 November 1978 in Mumbai. Jennifer died of cancer in 1984 which shattered him. After losing her to cancer, Shashi Kapoor fell into a deep depression that he never recovered from. The English actress Felicity Kendal is his sister-in-law.