Introduction: Chronic stress among medical students affects academic performance. Among the most established source of stress is academic-related stressors, such as exams. This study aimed to evaluate the prevalence of stress level, relationship between stress levels and academic performances among medical students at University of Cyberjaya. Methods: A cross-sectional online survey was conducted on 216 targeted respondents based on single proportion formula for sample size calculation. Data were collected using self-administered questionnaire to obtain respondents demographic and evaluate stress level using Perceived Stress Scale Questionnaire (PSS-10) and Medical Stress Questionnaire (MSSQ). Data were analysed using IBM SPSS Statistics for Windows, Version 23.0 and Spearman correlation analysis was used to determine the association between stress level and academic performance. Results: Of 216 targeted respondents, 197 (91%) responded, with majority (73.6%) aged 22 years and above. The majority of students (87%) felt stress within six months, having mild stress level (45.2%), moderate stress levels (40.1%), severe stress (8.1%) and low stress level (6.6%). Academic-related was found to be the most prevalent stressor (Score 2.43, SD 0.728). The relationship between perceived stress level and GPA showed a significant correlation at (r = -0.95, p<0.01) indicating the higher the stress level, the lower the academic performance. Conclusion: The prevalence of stress among medical students of UOC was high, and the higher stress level was significantly correlated with lower academic performance.