Purpose: The purpose of this paper is to examine the mediating effect of psychological contract breach on the relationship between job insecurity and counterproductive workplace behavior (CWB) and the moderating effect of employment status in this relationship.Design/methodology/approach: Data were collected from 212 supervisor–subordinate dyads in a large Chinese state-owned air transportation group. AMOS 17.0 software was used to examine the hypothesized predictions and the theoretical model.Findings: The results showed that psychological contract breach partially mediates the effect of job insecurity on CWB, including organizational counterproductive workplace behavior and interpersonal counterproductive workplace behavior. In addition, the relationships between job insecurity, psychological contract breach and CWB differ significantly between permanent workers and contract workers.Originality/value: The present study provides a new insight into explaining the linkage between job insecurity and negative work behaviors as well as suggestions to managers on minimizing the harmful effects of job insecurity.