Study Design. A cohort study.Objective. To investigate the association between psychosocial stress and low back pain (LBP)-related interference with daily living among college students.Summary of Background Data. Few longitudinal studies have examined the likelihood of developing LBP in the presence of a designated psychosocial stressor. All participants in the present study were suddenly affected by the Great East Japan disaster after enrolment in our cohort study.Methods. The present study was initiated among 95 students at Fukushima Medical University in January 2011. We assessed psychosocial stress in students using the Japanese version of the Perceived Stress Scale (JPSS). Follow-up surveys were conducted in July 2011 and May 2013, analyzing 94 students. Students were then divided into three groups (improved, -19 to -4; Maintained, -3 to +4; Aggravated, +5 to +22) based on the tertile points of JPSS change from baseline to 4 months after the disaster. LBP-related interference with daily living was assessed using the Brief Pain Inventory (BPI) questionnaire. Linear regression modeling was performed with BPI at 4 months after the disaster as the outcome, and JPSS change, sex, history of LBP, baseline physical activity, and baseline BPI as explanatory variables.Results. We found a significant increase in BPI score for the aggravated stress group (b coefficient, +0.79; 95% confidence interval, +0.06-+1.53), compared with the improved stress group. History of LBP and higher physical activity were also significantly associated with BPI.Conclusion. The present study suggests that perceived psychosocial stress induced by the disaster may be associated with LBP-related interference with daily living among college students in Fukushima.