The purpose of this study was to determine support for various tobacco-free policies among students in public universities. This cross-sectional study was conducted among 406 students from three main campuses of a university in July 2018. Three hundred ninety-two students responded from three campuses in Selangor. There was a significant association between knowledge of secondhand smoke (SHS) and the types of tobacco-free policies. Students who perceived knowing the dangers of SHS also supported smoke-free cars and campus policy. In conclusion, knowledge of secondhand smoke, third-hand smoke, and tobacco-free policies should be enhanced.