MEP (Mechanical,Electrical,Plumping) includes vast amount of equipment types and pipelines in the integrated design, leading the coordination of MEP design optimization a major challenge for complex buildings. This document explains the technical processes and characteristics of the three-dimensional MEP design optimization based on BIM(Building Information Modeling), connected with the case of the integrated pipeline optimization design practice of a hospital building. Though establishing the BIM model of four-space underground pipeline network system in a hospital outpatient building, we carried out MEP collision checking, obtaining three-dimensional spatial information 102 collision points. Combined with manual screening we finally identified 67 valid point of conflict, for the construction of secondary pipeline network optimization design. In particular, the suggestion on the promotion and application of BIM-based building MEP design to municipal pipeline network in the future is proposed.