Abstract: Product liability system has gone through several stages in its value orientation.At the early stage of capitalism contractual liabilities gave priority to efficiency.In early 20th century，fair value was emphasized by means of fault liability，warranty liability and presumptive fault liability.In the latter half of the 20th century，fairness was given priority by strict liability.And since 1990s，reform of strict liability suggested compromise between efficiency and fairness.Such changes in the value orientation of product liability system take place due to technological advancement，product abundance，and consumers′ strengthening consciousness of security.Reform of product liability system in China should focus more on social fairness so as to lay a stable and lasting foundation for greater efficiency.

Key words: product liability, fairness, efficiency, contractual liability, strict liability