For the purpose of equipment training, realistic training environments need to be built and makes operators having an immersed sense. Aiming at present military requirement for equipment operation training, a universal 3D modeling method for equipment training environment was put forward, which integrated with terrain, feature and special effect. The related key technologies such as terrain modeling flow, terrain model optimization, Large Area Database Management (LADBM) and particle system are also detailed. Finally, a simulation example was presented to prove the feasibility of the modeling method. It can provide beneficial reference for building realistic equipment operation training environment quickly.