Self-directed learning (SDL) has become an essential learning principle in medical curricula and a requirement of the professional accreditation standards. It has been advocated that SDL is an effective learning strategy for medical students to develop competence in knowledge acquisition and in promoting life-long learning. Although it has been presumed that problem-based learning (PBL) improves the learner's SDL readiness (SDLR), its effects arestill debatable. This study aimed to investigate the readiness for self-directed learning readiness (SDLR) among undergraduate medical students in problem-based learning (PBL) and non-PBL programs, examining the influence of gender, academic performance, and program year level. This cross-sectional study used a validated instrument, the SDLR instrument (SDLRI), to assess self-directed learning readiness. It consists of 20 items classified into the following four domains: learning motivation (six items), planning and implementation (six items), self-monitoring (four items), and interpersonal communication (four items) based upon a five-point Likert scale. Additionally, demographic data like academic year level, gender, and the student's final grade from the previous semester were collected. Questionnaires were administered to students in their first, third, and fifth (final) academic year across three different medical colleges in the United Arab Emirates (UAE). One of these colleges adopts a hybrid problem-based learning (PBL) approach, while the other two follow non-PBL programs. A total of 386 responses were collected, with 200 students (51.8%) from the hybrid PBL program and 186 students (48.2%) from the non-PBL programs. The overall mean SDLR score was 59.0±18.2. In both programs, the high-achieving students scored SDLR of 64.7±18.0 (n=112), which was statistically significantly higher than the eight medium- and low-achieving students, 57.8±17.2 (n=224). However, the overall SDLR score showed no significant difference in gender or between PBL and non-PBL programs. Although the SDLR increased as PBL students advanced in the program, it decreased in the non-PBL curricula. However, this difference was not statistically significant. The high-achieving students displayed a higher level of SDLR than 10 of the medium- or low-achieving students, regardless of the educational program. This highlights the essential effect of the intrinsic factor for undertaking SDL and implies that students should initiate the process. Moreover, enhancing personal development and SDL educational practices might be effective in improving SDLR if partly implemented in medical programs.