Background In the literature, immigrant victims appear to be more vulnerable to health effects of a disaster than indigenous victims. Most of these studies were performed without pre-disaster measurement and without using a control group. Aim The objective of the study is to monitor differences between two groups of victims, Turkish immigrants and indigenous Dutch, in utilization and morbidity as presented in general practice after a man-made disaster. Methods A matched cohort study was performed with predisaster (1 year) and post-disaster (4 years) measurements of patients from 30 general practices in Enschede. Turkish victims (N=303) and Dutch victims (N=606), matched on age, gender and socioeconomic status, were included. Main outcome measures were psychological problems and physical symptoms as recorded by the general practitioner, using the International Classification of Primary Care (ICPC). Results The Turkish victims showed higher utilization than the Dutch victims prior to the disaster. In the 1st postdisaster year, both groups of victims showed an increase in utilization, but the increases did not differ significantly. The Turkish group showed no significantly greater increase than the Dutch group in the five most prevalent clusters of health problems (psychological, respiratory, skin, musculoskeletal, and digestive). Conclusion The Turkish victims in general practice were as vulnerable as the Dutch victims for the effects on their health of this man-made disaster. Differences between Turkish and native Dutch victims of this man-made disaster can largely be explained by the differences that existed already before the disaster.