BackgroundMedical students are exposed to many serious healthcare-associated infections throughout their learning and training time particularly during a pandemic like COVID-19. Therefore, promotion of their knowledge, attitude, and practice regarding infection control measures is a mandatory action.ObjectiveThis study was executed to evaluate the knowledge, attitude, and practice of medical undergraduates toward infection control measures before and after the implementation of practical infection control training for them.MethodsA quasi-experimental prospective study was conducted on a simple random sample of medical undergraduates at Al-Qunfudah College of Medicine, Umm Al-Qura University, KSA. A total of 177 medical undergraduates were recruited for this study and completed a predesigned survey on their knowledge regarding infection control measures. Moreover, their practice of infection control measures was evaluated through a checklist before and 6 months after receiving practical infection control training during their academic year 2020–2021.ResultsA total of 177 and 176 responses were obtained at the pre-test and post-test, respectively. The mean ages of students who participated in pre-training and post-training assessments were (22.50 ± 1.02 and 22.03 ± 1.34), respectively with female sex predominance (62.1 and 61.9%). Mean knowledge and practice scores among them were enhanced from (7.79 ± 2.10 and 4.56 ± 2.58) at their pre-test to (11.06 ± 1.27 and 15.68 ± 1.90) at post-test (P-value 0.001 and <0.001), respectively. After training, almost all of them recommended infection control training for all medical students due to its great value.ConclusionThe training course has shown its capability in the promotion of medical undergraduates' knowledge, attitude, and practice toward infection control measures.