We examine the effects of uncertain demand on hotel capacity using the operation data of international tourist hotels in Taiwan from 1996 to 2008. Abel (1983) argued that demand uncertainty leads to an increase in the capacity of a firm if uncertain demand takes the form of output price uncertainty for the competitive market. We empirically test Abel’s model. Our findings support the demand uncertainty hypothesis in Abel’s model. Moreover, our results indicate that effective management of hotel capacities is a more important issue for managers of medium-sized hotels than for small or large-sized hotels in the Taiwanese hotel industry