In this paper, the laser frequency stabilization hardware system is built using an industrial computer, NI data acquisition card and peripheral optical path, and a set of digital frequency stabilization control software for single-frequency fiber laser is developed using LabVIEW FPGA. Based on the servo control signal generated by the modulated transfer spectrum, the 780 nm laser frequency is locked to the ultrafine jump spectral line of rubidium atoms by acquiring the error signal and controlling the piezoelectric ceramic expansion and contraction after PI processing. Allan variance results demonstrate that a short-term frequency stability precision of 1.52×10^-11 @10 s, and the long-term stability is better than 1.56×10^-11 @100000 s, with continuous operation for over 20 days. This digital frequency stabilization software employs a graphical programming language, which significantly reduces development cycles, presenting an intuitive and concise user interface for convenient analysis and processing. It has been successfully applied to the rubidium 87 fountain clock system and possesses versatility for applications in precision measurement fields such as atomic interferometers and laser gyroscopes.