For this study, we investigated the relationship between product diversification and firm performance using the panel data from 2005 to 2009 of property-liability insurers in China. The result indicated that product diversification is negatively related to the financial performance of property-liability insurers. This implies that product focus is a superior operating strategy for insurers. In other words, whereas insurers' product lines are more concentrated, a greater professional interest is indicative of greater financial performance of a company. Conversely, geographic diversification is also negatively related to the financial performance of property-liability insurers. This negative relation between geographic diversification and performance supports the strategic hypothesis. Moreover, while operating areas more concentrated, they improve a company's financial performance.