This study follows Stiroh (2006) to investigate the effects of revenue diversification on the average return and risk of Taiwan financial holding companies. The sample period is from 2007 to 2013 for 14 financial holding companies. Several empirical results are found. first, increasing noninterest income activity does not increase the average return of the entire financial holding industry. That is, there is no significant difference in average returns generated from noninterest and interest income activities. Second, for large financial holding companies, increasing noninterest income share tend to reduce the market risk. Third, the present study did not find sufficient evidence to support that an increase in noninterest income share would reduce the total risk of the overall financial holding industry.