Purpose Workplace bullying is a serious problem among nurses, which results in negative workplace behavior. Therefore, this study aims to understand how workplace bullying affects employees’ knowledge hiding behavior. Specifically, this study explored psychological contract breach as an underlying mechanism between workplace bullying and knowledge hiding; and learning goal orientation as a boundary condition between psychological contract breach and knowledge hiding. Design/methodology/approach The study collected data from 343 nurses working in the health-care sector of Pakistan on convenience basis using a questionnaire-based survey between December 2021 to March 2022. The data were analyzed through structural equation modeling. Findings The results revealed the adverse effect of workplace bullying on knowledge hiding behaviors among nurses, and psychological contract breach was noted to mediate this association. Further, learning goal orientation was noted to buffer the relationship between psychological contract breach and knowledge hiding. Research limitations/implications The cross-section design may restrict causality; however, the findings suggest health-care administration take appropriate measures to reduce the adverse effects of workplace bullying. In addition, the administration is suggested to implement training programs to make nurses capable of dealing with workplace stressors (bullying and psychological contract breach). Originality/value This research provides a novel perspective to consider psychological contract breach as a mechanism between workplace bullying and knowledge hiding in the health-care sector from the conservation of resources perspective. It further explored learning goal orientation as a buffer to mitigate the effect of psychological contract breach on knowledge hiding.