This book constitutes the refereed proceedings of the Seventh Theory of Cryptography Conference TCC 2010 held in Zurich Switzerland February 9-11 2010. The 33 revised full papers presented together with two invited talks were carefully reviewed and selected from 100 submissions.The papers are organized in topical sections on parallel repetition obfuscation multiparty computation CCA security threshold cryptography and secret sharing symmetric cryptography key-leakage and tamper-resistance rationality and privacy public-key encryption and zero-knowledge.