Abstract: The current state of AE technology for BOP testing in China was intreduced. Using the advantages of acoustic emission testing technology, success in building balance sheet for a lot of BOP in used, and count the rule based on analysis of a lot of different types BOP in use. According to the results of AE test, a focal point for BOP problems can be defined and the basis for the BOP to continue use and maintenance can be provided. This explains that acoustic emission technology is very successful in the BOP test.Some challenging problems and developing tendency are also described finally.