Objective: The objective of this study was to identify significant influences on physician recommendation for imatinib mesylate in chronic phase CML patients. Methods: Data were collected via a mail and Web survey of a random sample of 1,100 hematologists/oncologists. Physicians’ recommendations for imatinib were measured with a visual analog scale in response to a series of clinical vignettes. Linear multiple regression was used to test the model, with physician recommendations as the dependent variable. The independent variables included treatment characteristics, communication channels, physician characteristics, social system characteristics, and control variables. Results: A total of 305 responses was received, giving a response rate of 29%. The regression model was found to be significant. Perceived relative advantages in efficacy, peer influence, past experience, and academic affiliation were significant positive influences and transplant specialty was a significant negative influence on physician recommendation for imatinib mesylate in patients with chronic phase CML. Conclusion: Treatment characteristics, peer influence, and physician specialty had significant influences on physician recommendation for imatinib mesylate.