The purpose of this study aims to determine the effect of managerial ownership, institutional ownership, family ownership, and growth opportunities on accounting conservatism. The population in this study were transportation companies listed on the Indonesia Stock Exchange in 2017-2019. The sampling technique used was purposive sampling technique in order to obtain a sample of 32 company data that met the criteria. The data analysis used is multiple regression analysis, processed using SPSS program. The results of this study indicate that managerial ownership has no effect on accounting conservatism. Institutional ownership has a significant positive effect on accounting conservatism. Family ownership has no effect on accounting conservatism. Growth Opportunities has no effect on accounting conservatism.