Reasons of relieving and exempting liability is the important basis of confirming tort liability and the Tort Liability Law in China has system innovation in these reasons, which reflectes the legislative idea of fairness and justice, but whether on system level or on operational aspect, deficiencies still exist.Therefore, we must be based on China’s judicial practice and learn from foreign advanced experience in legislation,put reasons of relieving and exempting liabity into the constitution of tort liability,add principled rules, make vague rules clear, perfect concrete types, strengthen system combination, and at last realize the interest balance between remedies of victims’rights and maintenance of actors’ freedom on behavior.