Background: Approaches to admission into medical schools in Taiwan are diverse but primarily involve the Multi-Star Project (MSP), General Scholastic Ability Test (GSAT), and Advanced Subject Tests (ASTs). This study aimed to investigate the differences in time management ability between students admitted into medical schools through different approaches. Methods: The Time Management Disposition Inventory was employed in a questionnaire survey on 390 students from the 1st to 4th years of the School of Medicine at China Medical University to investigate their time management ability. Results: The valid response rate was 100%. According to factor analysis results, the items in the original questionnaire were divided into 3 factors. The total eigenvalue was 14.15; the total variance of the 3 factors was 90.1% and the Cronbach’s α = 0.934. According to the between-group comparison results, the MSP (adjusted mean = 3.924), GSAT (adjusted mean = 3.729), and AST (adjusted mean = 3.802) groups differed significantly only in their sense of time efficacy. Conclusions: Approaches of admission into universities profoundly affect medical students’ time management ability. Admission through MSP requires exceptional academic performance in 3-year high schools; therefore, the MSP group exhibited the highest sense of time efficacy out of all 3 groups. This enabled those students to effectively plan their short- and long-term learning and perform self-learning at all times. Admission through the GSAT or ASTs solely emphasizes one-time college entrance examination scores. Therefore, those students exhibited a relatively high sense of time value, which enabled them to achieve satisfactory performance in college entrance examinations.