Accelerated degradation is concerned with models and data analyses for degradation of product performance over time and at overstress and design condition. This paper presents an accelerated degradation model of adapters used for notebook E. It is assumed that output voltages of adapters degrade over time and their degradation rate is affected by temperature. An accelerated test is planned and implemented at three levels of temperature, and output voltages are measured periodically to estimate the degradation model. Based on the plot of test data, a degradation model is assumed which is based on the Anhenius model. Regression analysis is used to estimated the model, and analysis of variance is made to verify the significance of regression model. From the estimated model, the failure tjmes and acceleration factor are obtained.