Biosimilars are a cost-effective alternative to their originator biologics with the potential to increase access tobiological medicine and provide savings to the health care system. Currently, in Korea, there are few data on physicians’perceptions of biosimilars and reasons for either prescribing biosimilars or not. This study investigated the current levelsof prescribing experiences, perceptions, and willingness to prescribe biosimilars among specialist physicians in Korea. Anonline survey was conducted from July 30 to August 10, 2018. Responses were obtained from 200 healthcare professionalsacross the specialties of rheumatology, dermatology, gastroenterology, medical oncology, and surgical oncology. Mostrespondents (91.5%) had experience prescribing original biologics and 56.5% had experience in prescribing biosimilars. The main reasons for prescribing biosimilars were cost advantages and confidence in the efficacy and safety of biosimilars. Respondents showed positive views on biosimilars, with 71.5 and 83% confidence in interchangeability, efficacy, andsafety of biosimilars, but less confidence in switching from an originator biologic to a biosimilar. Based on the results ofthis study, a strategy for promoting biosimilar market entry could be prepared to enhance social benefits.