In order to solve the limitations of traditional reliability assessment methods and the shortcomings of common linear models in describing product degradation, a life prediction method is proposed, which is based on fault mechanism and stochastic linear degradation model. The failure mode and mechanism of the product are studied. The stochastic linear model is used to model and analyze the key performance parameters of the product. The maximum likelihood estimation method is used to solve the unknown parameters in the model, and then the life and reliability are predicted. The experimental result shows that the method has good prediction accuracy and a certain small sample processing capability, and has certain reference significance for the life and reliability prediction of electronic products.