Although outcomes of job insecurity have been extensively examined, researchers have paid significantly less attention to antecedents of job insecurity. However, in order to lessen and eliminate job insecurity, a deeper understanding of the sources of job insecurity is required. Among triggers of job insecurity, very few studies have examined workplace interpersonal relationships as predictors of job insecurity. To fill this research gap, we examine the relation between workplace mistreatment (i.e., workplace incivility, bullying, and abusive supervision) and job insecurity. Examining multiple forms of mistreatment also allows us to compare and contrast the relative impact of each workplace mistreatment on job insecurity. Furthermore, we identify a group of individuals who are particularly vulnerable to the negative impact of workplace mistreatment—those who are high in work centrality. Across two lagged survey studies, we largely found that work centrality exacerbates the relations of workplace incivility, bullying, and abusive supervision with job insecurity. Thus, this research contributes to the occupational health literature by demonstrating the relative predictive power of multiple forms of workplace mistreatment on job insecurity and identifying a vulnerable group who might suffer more from workplace mistreatment (i.e., those high in work centrality).