Background: Several states use certificate of need regulations (CON) to control the growth of acute-care services, but the possible association between these restrictions and the provision of cancer surgery has not been assessed. This study examines the association between acute-care CON, the availability of cancer surgery hospitals, and provision of six cancer operations. Methods: Medicare data were collected for beneficiaries treated with one of six cancer resections and an associated cancer diagnosis from 1989 to 2002. Hospital, procedure, and incidence rates for each cancer diagnosis were stratified by state and year. The number of hospitals performing each operation per cancer incident, the number of procedures performed per cancer incident, and hospital volume were compared between states with and without CON, and those that discontinued CON during the sample period were noted. Results: The number of hospitals per cancer incident was lower in CON states versus non-CON states for colectomy (P = .022), rectal resection (P = .026), and pulmonary lobectomy (P = .032). Hospital volume was significantly higher in CON states versus non-CON states for colectomy (P = .006) and pulmonary lobectomy (P = .043). There were no differences between states with and without CON in the number of procedures per cancer incident. Conclusion: Although use of cancer procedures was similar in CON and non-CON states, those with acute-care CON had fewer facilities performing oncologic resections per cancer patient. Correspondingly, average hospital procedure volume tended to be higher in CON states. These differences may have important implications for patient outcomes and costs.