Workplace mistreatment is a workplace stressor which has adverse effect on work outcomes. Due to its inimical consequences, an ample of research has been conducted during last few years to cope mistreatment at workplace. This study investigates the moderating role of psychological capital on the relationship between workplace mistreatment (workplace incivility, abusive supervision, workplace mobbing) and on-job behaviors (job performance, organizational citizenship behavior towards organization, organizational citizenship behavior towards individuals and counterproductive work behavior towards organization, counterproductive behavior towards individuals). Multisource data was collected through questionnaires from faculty members serving in universities in Pakistan. The data for independent variables i.e. workplace mistreatment and moderating variable i.e. psychological capital was collected from 408 faculty members in first step, the data for on-job behaviors (job performance, organizational citizenship behavior towards organization, organization citizenship behavior towards individuals) was collected from their supervisors and data for (counterproductive work behavior towards organization, counterproductive behavior towards individuals) was collected from their peers. The results of the study revealed that workplace mistreatment (workplace incivility, abusive supervision, workplace mobbing) has significant relationship with and job performance, organizational citizenship behavior towards organization, organizational citizenship behavior towards individuals. The results also revealed that psychological capital moderates the relationship between workplace mistreatment (workplace incivility, abusive supervision, workplace mobbing) and job performance, organizational citizenship xvi behavior towards organization, organizational citizenship behavior towards individuals. However, in case of counterproductive work behavior towards organization, counterproductive behavior towards individuals, diverse results are revealed. Guidelines and recommendations are provided to Higher Education Commission, Pakistan and university management to tackle workplace mistreatment in the universities in Pakistan. Future research directions are discussed