Abstract:  Different types of damage of the risers and subsea pipelines are summarized. The cause of the damage to the subsea pipe is summed up. The assessment methods and codes to check the different damage types are enumerated. The evaluation of surface defects is mainly to evaluate whether the surface defect degree of damaged subsea pipe meets the specification requirements. The evaluation of mechanical strength can tell us whether the local stress is exceeding the requirements of the code; the finite element method is used to simulate the overall pipeline stress, so as to judge whether the overall pipeline strength meets the specification requirements. Through the above evaluation methods, we can judge whether the subsea pipe can continue to operate after damage. It effectively solves the problem of in-service pipeline damaged structure evaluation, providing a reference for the project decision.