The existing research on bottom-line mentality has mainly focused on understanding why it leads employees to unethical behaviors. The current study aimed at understanding why, how, and when supervisor bottom-line mentality (SBLM) discourages positive employee behavior (e.g., voice, and innovative work behavior), which is an under-researched area. While doing so, this study utilized the tenets of conservation of resource theory to explain the impact of SBLM. The study also identified psychological safety as the underlying mechanism of SBLM-employee positive behavior relationship. In addition, grit has been proposed in this study as the boundary condition of this relationship, which has not yet been studied with SBLM. The data from 156 respondents were collected using a self-administered questionnaire and non-random sampling. The confirmatory factor analysis was conducted using AMOS 23, and hypotheses were tested through ordinary least squares (OLS) regression analysis using SPSS Process Macro. The results supported the study hypotheses by showing that SBLM significantly affected employee voice, innovative work behavior, and psychological safety in the proposed direction. In addition, the mediation of psychological safety and moderation of grit were also supported. The study also provides important theoretical contributions and implications for managers and policymakers.