Background Cardiac point-of-care ultrasound (POCUS) training has been integrated into medical school curricula. However, there is no standardized cardiac POCUS training method for medical students. To address this issue, the American Society of Echocardiography (ASE) proposed a framework for medical student cardiac POCUS training. The objective of this pilot study was to develop a medical student cardiac POCUS curriculum with test scoring systems and test the curriculum feasibility for a future definitive study.Methods Based on the ASE-recommended framework, we developed a cardiac POCUS curriculum consisting of a pre-training online module and hands-on training with a hand-held ultrasound (Butterfly iQ). The curriculum learning effects were assessed with a 10-point maximum skill test and a 40-point maximum knowledge test at pre-, immediate post-, and 8-week post-training. To determine the curriculum feasibility, we planned to recruit 6 pre-clinical medical students. We semi-quantitatively evaluated the curriculum feasibility in terms of recruitment rate, follow-up rate 8 weeks after training, instructional design of the curriculum, the effect size (ES) of the test score improvements, and participant satisfaction. Discriminatory ability of the test scoring systems were assessed by comparing the scores of the medical students, medical interns, and experts.Results Six pre-clinical medical students participated in the curriculum. The recruitment rate was 100% (6/6 students) and the follow-up rate 8 weeks after training was 100% (6/6). ESs of skill and knowledge test score differences between pre- and immediate post-, and between pre- and 8-week post-training were large. The students reported high satisfaction with the curriculum. The test scoring systems demonstrated excellent discriminatory ability between the 3 different performance levels.Conclusions This pilot study confirmed the curriculum design as feasible with instructional design modifications including the hands-on training group size, content of the cardiac POCUS lecture, hands-on teaching instructions, and hand-held ultrasound usage. Based on the pilot study findings, we plan to conduct the definitive study with the primary outcome of long-term skill retention 8 weeks after initial training. The definitive study has been registered in ClinicalTrials.gov (Identifier: NCT04083924).