To address the insufficient configuration of real-time measurement devices in distribution networks, a state estimation method for distribution networks based on a CNN-BiLSTM network and a customised HGGA algorithm is proposed. First, the historical data and real-time data are used as the input of the CNN-BiLSTM network to obtain the branch power pseudo measurement and load node injected power pseudo measurement with high accuracy at the current moment. Second, the pseudo measurement set of the input state estimation is determined using the customised HGGA algorithm. Finally, the real-time measurement, pseudo measurement, virtual measurement, and weight set are input into the state estimation program to complete the real-time state estimation of the distribution network based on the weighted least squares method. Additionally, the proposed method is applied to the data fusion of different measurement systems. Theoretical analysis and example verification confirm that the proposed method can effectively improve the accuracy of pseudo measurement modelling and state estimation results.