The invention provides a numerical control sliding table saw control system comprising a serial communication module, an operation mapping module and a PLC communication protocol module, which are located in a working position computer. The operation mapping module is used for calculating different size deduction data according to different rules of to-be-processed plates and mapping operation commands into PLC commands which can be identified by a PLC. The PLC communication protocol module is used for packing of the PLC commands and the unpacking of reply information of the PLC. With the PLC commands, the PLC controls a server connected thereto to automatically adjust the position of a caliper on a sliding table saw and the plates are pushed to the position determined by the caliper for processing. According to the invention, a worker only needs to push plates to the caliper position for processing and no manual calculation and adjustment is needed, so that the error rate is reduced, the dependence on manual operations is reduced and the processing efficiency is increased.