Purpose: The servo motor for mobile robots is a key component of the driving parts of industrial robots. Analysis of major failure factors of servo motors and analysis of life characteristics can be used to predict the life of a mobile robot.<BR>Methods: A failure analysis of servo motors for mobile robots is prepared through literature and expert opinions, and major failure modes are identified. In addition, the accelerated life test is performed, and the performance degradation of the servo motor is estimated by analyzing the test results.<BR>Result: FMECA was created through failure analysis, and major failure modes were identified. Through the analysis of the results of the accelerated life test, the life distribution of the servomotor for the mobile robot was confirmed and its suitability was verified.<BR>Conclusion: Life characteristic value of servo motor for driving mobile robot such as Weibull distribution and shape parameters calculated by verifying the suitability of the life distribution of a servomotor for a mobile robot are applied to calculate the warranty life of the servo motor.