Aim(s) This paper examined the impact of workplace bullying (WPB) on mild aggressive deviant behaviour, such as knowledge hiding and employee time theft, in Pakistani health care institutions. Additionally, this study investigated the mediating role of negative emotions on the relationship between WPB and its outcomes. Background Although mild deviant behaviour has been proven to affect the health care sector, its antecedents are still untapped. Method Data were collected from 233 nurses working in hospitals located across Pakistan via self‐administered questionnaires in three time lags to test both the direct and indirect effects of WPB. The hypothesized correlations were tested using structural equation modelling (SEM). Results The results revealed that WPB increased knowledge hiding and employee time theft amongst nurses. The indirect effect of negative emotions was established on the aforementioned relationships. Conclusion This study contributes to the existing literature by concentrating on predictors that trigger deviant behaviour amongst nurses. It also assessed the mediating impact of emotions, wherein such endeavour is essential for researchers and practitioners. Implications for Nursing Management The study outcomes are significant for the hospital sector to improve their strategies, such as implementing resilience during stressful events to address WPB and deviant behaviour amongst nurses.