The purpose of this study is to examine and provide empirical evidence of the effect of personal cost, professional commitment, and seriousness of wrongdoing on whistleblowing intention, as well as the impact of legal protection in influencing as a moderating variable. The populations of this study are civil servants (ASN) from the Directorate of Construction Services Procurement, the Directorate General Of Construction Development in Ministry of Public Works and Housing (MPWH). The sample of this study are 90 respondents, obtained using a saturated sampling technique. The questionnaire data of this study are analyzed using the Statistical Package for Social Sciences (SPSS). The result shows that civil servants consider their personal cost and the seriousness of wrongdoing as they intend to blow the whistle. Yet, the study finds that professional commitment does not affect civil servant’s whistleblowing intention. The study also finds that legal protection is only able to moderate the effect of personal cost and professional commitment on whistleblowing intention and is unable to moderate the seriousness of wrongdoing. These findings help to obtain insight regarding the policy that can improve whistleblowing intention.