The invention discloses a top drive simulation system and a method. The simulation system comprises top drive simulation operation equipment, a PLC (programmable logic controller) and a control unit, wherein the control unit comprises a main control machine, a parameter machine and a graph processing machine; the top drive operation equipment is connected with the PLC; the PLC is connected with the parameter machine through a serial port, and the parameter machine and the graph processing machine are respectively connected with the main control machine through a communication network. The simulation method comprises the following steps that S1, switch and knob state data are collected; S2, the data are sent to the main control machine; S3, the main control machine carries out calculation; S4, virtual showing is carried out. The invention provides the top drive simulation system and the method. The system has the advantages that the occupied ground is small, the maintenance cost is low, the damage cannot easily occur, the full-dimension and full-physical operation environment can be provided, the strict underground mathematical simulation is adopted, so the system and the method conform to the real process requirements, and meanwhile, the system has the top drive work principle 3D (3-dimensional) animation display function, so that trainees can better understand the top drive work principle and a wearing part maintenance method.