This study employs the three-point estimation method to calculate the stochastic power flow in distribution networks, develops a corresponding model, and validates the method under conditions of load variations and fluctuations in distributed generation output. The objective is to derive the statistical distribution of key operating parameters such as voltage, current, active power, and reactive power and to analyze the distribution characteristics of network power flow. The proposed methodology employs the three-point estimation approach to determine the moments of target random variables based on the known probability distributions of input variables, subsequently deriving the probability distributions of the output variables. Applying this method to stochastic power flow calculations offers the advantage of simplifying computations while maintaining high accuracy, significantly reducing computational burden.