Waste management in Semarang State University (UNNES) environment has been carried out by cooperation from various parties. College student knowledge about waste management becomes very important, because college students are one of the campus residents who produce a lot of waste. The purpose of this study was to determine college student knowledge about waste management that occurred in UNNES campus environment, while the intended waste management was 3R-based waste management consisting of (reduce, reuse, and recycle). This study uses a quantitative approach with percentage descriptive analysis techniques. The population in this study were UNNES college students consisting of 8 faculties and 1 postgraduate program. The sampling technique uses proportional random sampling technique. Data collection techniques using questionnaires, observations and documentation studies in the form of previous research related to this research. The results showed that, 1) The college students' knowledge about sorting waste between organic waste and inorganic waste was at a high criterion with an average score of 20,79. With a breakdown of the causes of the difference in knowledge they get is due to the amount of information and level of education obtained. 2) College students' knowledge about waste management based on 3R, namely reuse is included in the high category, reduce is included in the high category, then recycle is included in the high category.