This research aims to: (1) find out the condition of male and female students’ characters at Ibnul Qayyim Islamic Boarding School Yogyakarta, (2) find out the description of iqab implementation management at Ibnul Qayyim Islamic Boarding School Yogyakarta, and (3) find out how big the influence of iqab toward Students Character Formation at Ibnul Qayyim Islamic Boarding School Yogyakarta. The type of this research was mixed of descriptive quantitative and associative-causal research. The research subjects were the students of Ibnul Qayyim Islamic Boarding School Yogyakarta. The data collection used interviews, documentations, and questionnaires. The data analysis technique used was descriptive statistical analysis and simple linear regression analysis. The research result shows that 1) the condition of male and female students’ characters at Ibnul Qayyim Islamic Boarding School Yogyakarta is in good category shown by the character percentage of 74.69%. 2) The description of of iqab implementation management at Ibnul Qayyim Islamic Boarding School Yogyakarta if observed from: (a) the ratio of violation types done by the students shows that the comparison of major: moderate: minor is 15.95%: 51.86%: 55.14%. (b) The effectiveness of iqab seen from the data on violation level of the students reaches 40.98%, and it means that the iqab implementation is effective to reduce the violation level of the students during their stay in the Islamic boarding school. (c) The data on the impacts caused by the iqab implementation show that the positive impacts of the iqab implementation is bigger that is 69.3% compared to the negative impacts that is 34.4%. It means that iqab brings positive impacts for the students. 3) There is influence of iqab toward Students Character Formation at Ibnul Qayyim Islamic Boarding School Yogyakarta. It is shown by the t-count which is bigger than t-table (8.767>1.972). Additionally, the value of iqab influence toward the characteristics formation of 0.280 or 28%. Keywords: Iqab, Character