Nurses' skills and confidence in providing oral care to patients play important roles in healthcare. Studies have proved that peer-to-peer learning and assessment can help improve nurses' skills and confidence. However, no study has investigated it using an objective assessment checklist. This study investigated an oral hygiene practice training program for nursing students. It focused on their oral healthcare skills, confidence, and perspectives regarding implementing an objective structured clinical examination (OSCE). A pre- and post-survey of 97 nursing students from a nursing school in Japan was conducted as a peer-to-peer oral health education training program that included an assessment and performance checklist. Confidence in performing and assessing oral care significantly improved after attending the program. Furthermore, the changes were significantly greater in the developed program than in the training program without the checklist. The mean total assessment scores (0-25) of the first, second, third, and fourth participants in the four-student groups were 22.1, 23.4, 23.9, and 24.1, respectively. The mean scores of the second, third, and fourth participant groups were significantly higher than that of the first participant group (p < .01). Fifty-two positive and 58 negative comments were received regarding the implementation of the program with professional assessments and the checklist. The most common positive comment mentioned that the evaluation by professionals improved oral care learning and skills. This study developed a program to improve nursing students' confidence and oral care delivery skill building in an OSCE-style delivery.