In light of the safety concerns arising from the significant impact of degradation failure in the reaction wheel, which is an essential actuator in satellite attitude control systems, this study aims to predict the extent of temperature degradation and the reliability of the reaction wheel. To achieve this objective, various uncertain factors in degradation modeling were thoroughly analyzed and considered. Utilizing the recursive algorithm of the Kalman filter, the model based on the Wiener process for degradation modeling was employed to predict the reliability of the reaction wheel in the presence of degradation faults. The analysis results indicate that the predictions for temperature degradation and reliability of the reaction wheel are generally accurate. These significant findings play a pivotal role in providing indispensable decision support for the maintenance and effective management of the reaction wheel. Moreover, they establish a robust technical foundation that contributes to the continual enhancement of satellite system safety.