Abstract: Technological diversification has a impact on the choice of company’s product innovation strategy and its performance, however the existing literatures have not analyzed on how the mechanism of technological diversification impacts corporate performance; in the meantime, the relative empirical analysis based on Chinese companies are also lack. Based on the latest theoretical research and the results of on site research, the mediative mechanism betwee corporate technological diversification and its performance is studied from a angle of product innovation strategy. The empirical results suggest that poruct innovation strategy has completely played a mediative role in the impact of corporate technological diversification on its business performance, but only has played a partially mediative role in the impact of corporate technological diversification on its innovation performance.