Green Campus is a campus environment that is designed to increase energy efficiency, preserve resource and improve the quality of the environment. One of the important elements to support the green campus program is the existence of drinking water supply system.Universitas Gadjah Mada Drinking Water Supply System (UGM-DWSS) is a drinking water or potable water supply service to supply drinking water for the campus. This research aims at analyzing UGM-DWSS potential and its performance to support Green Campus. This research was based on primary data collection in UGM campus. Data collection techniques consist of observation of UGM-DWSS facilities, interview with UGM-DWSS water managers and users, and questionnaires distribution to UGM academic community. The daily water production of UGM-DWSS was 10 l/s drinking water. Every day the water discharge distributed from UGM-DWSS to 49 water fountains and 12 water dispensers was1.71 l/s, while the estimated daily water consumption rate was0.07l/s. It is assumed that those who did not consume water from UGM-DWSS facilities bought plastic drinking water bottle. Every day, it is estimated that the number of generated plastic drinking water bottle waste was 19,168 bottles with capacity 600 ml/bottle. Indeed, by comparing to the total water production capacity being produced daily, the idle capacity was 99.3 %.The tendency of negative response from the majority of UGM inhabitants for using UGM –DWSS was due to hesitation about water quality, continuity of water supply, and ease of access to the nearby water fountains and water dispensers. Improvement of UGM-DWSS facilities that are supported by massive socialization programs including innovation to utilize produced drinking water is recommended to optimize the role of UGM-DWSS to create Green Campus.