Abstract: In order to reduce the machining errors caused by the fixture in the processing of agricultural machinery parts, it introduced NX software 3 D modeling and assembly simulation technology into the fixture design process, and introduced neural network intelligent algorithm to analyze the various machining errors caused by the fixture, and then reduce the errors. Finally, through the 3 D modeling and virtual assembly simulation of the fixture parts, it is verified that the intelligent algorithm reduces the error. It found that the neural network algorithm can significantly reduce the processing error caused by the fixture and improve the processing accuracy of agricultural machinery parts.