PURPOSE: To obtain the three-dimensional model generation system which can easily generate a three-dimensional model by synthesizing initial data on the three-dimensional model from an existent system diagram and a plan.

CONSTITUTION: This system is equipped with a facility property management system 2 having a facility drawing subsystem 2A which edits, stores, and manages drawing information regarding the piping, wiring, and facilities of a building, a facility ledger subsystem 2B which inputs, stores, and manages attribute information on the piping, wiring, and facilities of the building, and a material subsystem 2C which edits, stores, and manages material information regarding the piping, wiring, and facilities of the building, and a three- dimensional piping system 10 which generates the three-dimensional model representing geometric information and connection information on the three- dimensional piping, wiring, and facilities in the building from plans by floors having geometric information regarding the piping, wiring, and facilities of the building and the system diagram having logical connection information on the floors based on the respective data on the drawings, ledgers, and materials managed by the facility property management system 2.