Objective: This study aimed to examine the prediction of counterproductive work behavior (CWB) by Dark Triad personality traits (DTPT) and the mediating role of daily hassles, in order to gain a better understanding of the factors influencing organizational productivity and to provide practical strategies for improving the workplace environment.

Method: This study employed a descriptive-correlational design. The statistical population included all employees in the private and public sectors of Mashhad city in 2023. The sample group consisted of 250 individuals, selected through convenience sampling. Using the convenience sampling method may limit the generalizability of the findings to the entire target population. Data were collected using valid questionnaires, including the DTPT Questionnaire by Jonason and Webster (2010), the Counterproductive Work Behavior Questionnaire by Golparvar and Khaksar (2008), and the Daily Hassles Questionnaire by Junqueira-Silva et al. (2020). Data were analyzed using Smart-PLS software to assess direct and indirect effects, as well as the fit of the research model.

Findings: The results showed that DTPT have a direct and significant effect on CWB (β=0.42). Additionally, daily hassles played a significant mediating role between DTPT and CWB (β=0.35). The research model exhibited a good fit (SRMR=0.065), indicating a high correlation between the variables.

Conclusion: The findings indicate that focusing on negative personality traits and daily hassles can help prevent CWB and improve productivity. Therefore, it is recommended that organizations design training programs to manage negative personality traits and reduce stress caused by daily hassles to enhance productivity and improve the work environment.