The purpose of this study was to investigate the influence of hostile attribution style (HAS) on the processes linking job stressors and CWB. Self and peer data were collected via online questionnaires from employed participants recruited from undergraduate classes and non-student employees. Using data from 147 dyads of employees and coworkers, the effects of HAS on three areas were examined: the influence of HAS on the appraisal of psychosocial (incivility, interactional justice, and interpersonal conflict) and nonsocial (organizational constraints and workload) stressors; HAS as a moderator of the link between stressors and CWB; and HAS as mediator of the link between CWB and the individual difference variables of negative affectivity (NA), trait anger, and Machiavellianism. Regarding appraisals, HAS was more strongly related to psychosocial stressors than to workload (nonsocial stressor). However, results regarding the comparisons of the HAS-psychosocial stressor correlations with the HAS-organizational constraints (nonsocial stressor) correlations were mixed. Moreover, contrary to what was hypothesized, correlations of HAS with interpersonal constraints and job context constraints were not significantly different in magnitude. HAS was shown to moderate the relationship between CWB and the stressors of interpersonal conflict and organizational constraints. Individuals high on HAS engaged in more CWB when stressors were high, whereas individuals low on HAS engaged in low levels of CWB overall. HAS partially mediated the relationship between NA and CWB, in addition to the relationship between trait anger and CWB. It fully mediated the relationship between Machiavellianism and CWB. The influence of Machiavellianism on the occupational stress process also was explored. It was expected that high Machiavellians would appraise and respond to stressors in a negative fashion. However, contrary to what was expected, Machiavellianism was positively associated with informational justice and negatively related to incivility and CWB. Furthermore, it was negatively associated with NA and HAS. An alternative explanation for the results regarding Machiavellianism was presented. Although all hypotheses regarding the effects of HAS were partially supported, results of this study were generally demonstrative of the merits of including attributional processes (i.e., hostile attribution style) in CWB research within the occupational stress framework.