OBJECTIVES: This study investigated the clinical characteristics and functional magnetic resonance imaging (fMRI) findings of firefighters suffering from partial posttraumatic stress disorder (partial PTSD). They were treated by eye movement desensitization and reprocessing (EMDR) and the treatment effect was evaluated. METHODS: A total of 116 firefighters were screened and 15 of them were diagnosed as partial PTSD. 1) We compared sociodemographic and psychological characteristics between the firefighter partial PTSD group and the firefighter control group. 2) Subjects in the firefighter partial PTSD group (n=10), firefighter control group (n=8), and general control group (n=12) underwent fMRI with traumatic, negative, positive, and neutral picture stimuli. We compared clinical characteristics and fMRI findings among these three groups. 3) Seven firefighters in the partial PTSD group were treated by EMDR and the treatment effect was evaluated according to psychological scales. RESULTS: In fMRI analysis, there was a left middle temporal/occipital activation in the order of the general control group, firefighter control group, than the firefighter partial PTSD group for the Traumatic-Baseline contrast. For the Negative-Baseline contrast, there was an increased left middle temporal/occipital activation in the general control group versus decreased activation in the firefighter control group and the firefighter partial PTSD group. All firefighters in the partial PTSD group treated by EMDR showed significant improvement of Clinician-Administered PTSD Scale scores. CONCLUSION: These results show high incidence rate of partial PTSD in firefighters. In addition, partial PTSD firefighters exhibited distinct clinical characteristics and fMRI findings and showed significant improvement by EMDR treatment.