Objective: Medical emergency personnel can experience psychological and physical stress daily. One of the ways to deal with stress is to have problem solving and decision making skills. The purpose of this study was to determine the effect of decision-making and problem-solving training on occupational stress of medical emergency personnel in Gonabad. Method: In this quasi-experimental study (2017), 60 employees of Gonabad Center of Medical Emergencies randomly assigned into two groups of intervention and control. The intervention group received six sessions of problem-solving training in the form of lecture, question and answer, and group discussion planned according to D'Zurilla and Goldfried protocol, while the control group did not receive any intervention. At baseline and end of the study, both groups filled ENSS. The collected data was analyzed using SPSS 20 software, independent t-test and Chi-square test (P<0.05). Findings: each group contained 30 samples who had no significant difference in terms of underlying features (p>0.05). The mean score of occupational stress was not significantly different in two groups before intervention (P=0.58), while there was a significant difference between two groups after the intervention (P<0.001). However, the mean difference before and after intervention was statistically significant in both groups (P<0.001). Thus, the mean score of occupational stress increased in the control group and decreased in the intervention group. Conclusion: According to results, decision-making and problem-solving training as a short-term psychological intervention can help reduce occupational stress of people working in medical emergency services.