In view of the low reliability level of the hydraulic cylinder used for excavator in our country,the research on the reliability test and evaluation method of the hydraulic cylinder used for excavator is lacking,taking the bucket rod cylinder of 2.1×105 N excavator with large market holding capacity as the test object,various reliability tests,such as reciprocating test,pulse test,overloading test,were carried out.The performance index data of the test process and the disassembly analysis data of the key parts were collected,then the test data were compared with the test data of the actual sample parts,to verify the rationality of the test method and the accuracy of the test data,and to verify the relationship between the test method and the test time of the hydraulic cylinder of the excavator and the working time of the actual working sample.The results show that the 10 000,20 000 times of pulse test and 300 000,500 000 times of reciprocating test can correspond to the 1 000 h,2 000 h of actual working time.It provides reference for the study of reliability test and evaluation method of hydraulic cylinder of excavator.