We propose a time-of-flight ranging method by measuring the pulse laser phase based on field-programmable gate array (FPGA) digital mixing, in which accurate laser ranging with a total digital system is realized by combining one FPGA chip with a simple laser transmitting and receiving circuit. The system has the advantage of simple structure, reliable operation, low manufacturing cost and easy integration. Experimental results show that compared with the pulse laser ranging method using commercial time-to-digital converter chips, it can realize precise measurement of distance, and the measurement error can be significantly reduced. In addition, this method has better performance of ranging accuracy.