Abstract: The wall thickness thinning rate and ellipticity are selected as evaluation criteria for the free bending forming results of the pipe. The influencing factors include the gap between the bending die and the pipe, the radius of the corner of the bending die, the length of the bending deformation zone of the pipe, the radius of the corner of the guide mechanism, and the gap between the guide mechanism and the pipe. A sample library for the evaluation criteria and influencing factors of free bending of pipes is established using numerical simulation method. Six random groups are selected as test samples, while the remaining samples are used for training. The POA-BP neural network prediction model is constructed by combining the BP neural network and the Pelican optimization algorithm to predict the free bending forming results of pipes. The results show that the maximum prediction error of the wall thickness reduction rate and ellipticity of the POA-BP prediction model does not exceed 2%. Therefore, the POA-BP prediction model can effectively predict the pipe forming results.