This research was conducted with the aim of investigates the relationship between participation in decision making and job tension by considering the mediating role of procedural justice and interpersonal mistrust. The population included the male employees of an industrial and productive company (800 persons) in Isfahan city, among whom 211 persons were selected (from the names list of personnel) using simple random sampling. The research instruments comprised job tension index (Kahn et a1, 964), procedural justice scale (Moorman, 1991), interpersonal mistrust questionnaire (Miller, 1991) and participation in decision making (Miller, 1991). Data were analyzed by using of Pearson correlation coefficient, structure equation modeling (SEM), mediation regression analysis and Sobel’s test. The results of structure equation modeling revealed that participation in decision making accounted for 6.4 percent of variances of procedural justice, but there was no significant relation between participation in decision making and interpersonal mistrust (P>0.05). Procedural justice also described 17.3 percent of variances of interpersonal mistrust. Finally, procedural justice and interpersonal mistrust, accounted 24.7 percent of variances of job tension. Mediation regression analysis showed that procedural justice played the complete mediator role in relations to decision making, interpersonal mistrust and job tension. But interpersonal mistrust played a partial role in relation to procedural justices and job tension.