Superconducting Nanowire Single-Photon Detector (SNSPD) is the core detection device in the current quantum technology field. Featuring extreme performance including near-infrared detection efficiency greater than 90%, dark count rate lower than 10 Hz, and time resolution less than 20 ps, it has become a core supporting facility for cutting-edge fields such as quantum secure communication, deep-space laser communication, quantum computing, quantum precision measurement, and biological single-molecule fluorescence detection. The high-voltage bias power supply serves as a key supporting component of the SNSPD system, delivering precise, stable and ultra-low-noise DC bias voltage for superconducting nanowire devices. Its output noise level, voltage stability, ultra-low temperature adaptability and anti-interference capability directly determine the core performance indicators of SNSPD including detection efficiency, dark count rate and time resolution, and even govern the encoding rate and communication distance of the entire quantum system. SNSPD systems impose far stricter requirements on high-voltage bias power supplies than conventional precision power supplies. On the one hand, the superconducting nanowires of SNSPD usually operate within the liquid helium temperature range of 2.1 K to 4.2 K, and some high-performance devices even work in dilution refrigerators below 100 mK. Part or all components of the bias power supply need to operate stably under extreme ultra-low temperatures, while traditional power supply devices suffer severe performance degradation, parameter drift and even startup failure at ultra-low temperatures. On the other hand, the bias current of superconducting nanowires operates at 90%~99% of the superconducting critical current. Tiny noise and fluctuations in the bias voltage will directly cause false triggering of devices, a sharp rise in dark count rate, and even loss of single-photon detection capability. It is required that the peak-to-peak ripple of the power supply output voltage is less than 10 μV, the voltage noise density is lower than 10 nV/√Hz@1 kHz, and the long-term stability of the output voltage is better than ±1 ppm/8 h. In addition, SNSPD systems generally operate in strongly electromagnetically shielded low-temperature environments. The power supply must adapt to the wiring constraints, ultra-low heat dissipation requirements and electromagnetic compatibility demands of quantum systems. Conventional precision linear power supplies and switching power supplies have critical drawbacks including poor ultra-low temperature adaptability, high output noise, excessive heat generation and strong electromagnetic interference, which cannot meet the extreme performance requirements of SNSPD systems. The relevant design must strictly comply with standards such as GB/T 4793.1