Background: In everyday life the human body experiences physical and psychological stress. Physical stress is related to the body carrying out physical activity, while psychological stress is related to a person's condition in interpreting situations in life. In teenagers at college level, stress can occur due to busy lecture activities, causing fatigue. Fatigue is associated with increased levels of lactic acid in the blood. The aim of this research was to determine the relationship between lactic acid levels and psychological stress levels. Method: This research was a cross sectional study conducted on 27 6th semester students. Lactic acid levels were measured using the Roche brand Accutrend and General Health Questionnaire -12 (GHQ-12) to measure psychological stress levels. Results: From the results of the analysis using Pearson Correlation, the p value = 0.268 (p> 0.05), correlation coefficient (r) = 0.221, and the direction of the relationship is +. Discussion: Psychological stress is not in harmony with high levels of lactic acid in the blood. Conclusion: There is no relationship between lactic acid levels and psychological stress.