Abstract: In view of problem that detailed reliability calculation method of roof beam of hydraulic support has large amount of calculation, a reliabillty approximation calculation method of roof beam of hydraulic support based on neural network model was proposed. Neural network model for reliability approximation calculation of roof beam was established. The back propagation algorithm is used as weight learning algorithm, and square type function is used as error function. Taking roof beam of ZY18000/25/45D hydraulic support as an example to calculate the reliability, the results show that relative error of roof beam reliability calculation is within 6.3%.