The invention discloses an intelligent assembly process design method based on morpheme division and an artificial neural network. The method comprises two parts of assembly process knowledge expression and assembly process knowledge reasoning, and mainly comprises the following steps of: 1) dividing assembly process knowledge morphemes; 2) constructing, storing and expressing an assembly structure tree; 3) constructing an assembly process knowledge base; 4) calculating and comparing assembly structure tree structure similarity; 5) carrying out multi-constraint matching and retrieval on the assembly process knowledge; and 6) matching the intelligent weight adjustment with the auxiliary knowledge of the artificial neural network training model. According to the method, repeated manual laborof technicians can be reduced; the error-tolerant rate in the process design engineering is improved; the time cost in an assembly process design project is saved, the production efficiency is improved, and meanwhile, in order to establish an assembly process knowledge base, in combination with the reasoning ability of people and support an automatic assembly process design method, more comprehensive and effective guidance can be provided for assembly process design, and the assembly process design efficiency and accuracy are improved.