The invention discloses a direct-current power distribution and utilization system reliability evaluation method based on network equivalence, and relates to the field of direct-current power distribution systems. According to the method, the problem of repeated enumeration process of the fault state in the fault mode consequence analysis method is solved. Aiming at original parameters and a topological structure of a direct-current power distribution and utilization system, load parameters of the power distribution and utilization system, a fault rate of key equipment and fault repair time, upward equivalence and downward equivalence of the direct-current power distribution and utilization system are respectively applied to decompose the system into N simple radiative networks; and determining an equivalent scheme according to the to-be-evaluated load node, and evaluating the reliability index of the power distribution system according to the load point reliability index. The method avoids the repeated and tedious enumeration process of the fault state of the power distribution system, improves the reliability evaluation efficiency, and guarantees the accuracy of the reliability evaluation result to the maximum degree. The method is suitable for a direct-current power distribution system and has good accuracy and high efficiency.