With the reform of marketing and information technology, short life cycle has become the important feature of modern products. Thus the third party IWOM's impact on production has changed. Based on the hypothesis of persuasion, knowing, silencing helix and adjustment effect, this paper constructs the impact mechanism of the third party IWOM on the sales of shortlifecycle products. Through the heteroscedasticity test and FGLS estimation method, this paper takes movies for example to carry on the empirical test. The results show that the main effect of the thirdparty IWOM on the short life cycle products is the persuasion effect and the silent helix effect. Then, it is suggested that the marketing strategy of shortlifecycle products should focus on scoring mechanism and followup maintenance strategy.