This research aims to examine the influence of ewuh-pakewuh culture, attitude, perceived behavioral control, personal responsibility for reporting, and personal cost of reporting on the whistleblowing intentions among civil servants in the Directorate General of Taxation and perceived organizational support as moderation variable. This research uses primary data collected through the questionnaire. The data analysis is Structural Equation Model (SEM) with SmartPLS 2.0 software. This study employs a whole population as sample resulting 117 employees of Directorate General of Taxation. This research is divided into two scenarios: less serious corruption case and serious corruption case. The results of this research indicate mixed results. It seems that level of violation might affect the result.