The single point discharge system has emerged in order to meet the stricter and stricter requirements of the ocean pollution prevention for drilling rigs. The main design concept is to integrate the related discharge pipelines of the drilling rig to one discharge pipeline, that is, the single point drainage. The single point discharge system of a jack up drilling rig has been elaborated and analyzed. It can be used as referenc for the design of the single point discharge system for other drilling rigs.