The invention provides a data flow diagram mapping method and device, wherein the method comprises: acquiring a data flow diaphragm to be mapped; acquiring a computing array including multiple processing units; according to a pre-trained mapping quality model, a mapping priority, a data flow diaphragm matrix and the computing array, sequentially determining quality information of a mapping state of the data flow diagram when each operator node is mapped to at least one processing unit; according to the quality information of the mapping state of each operator node, determining the target mapping processing unit which the operator node maps to the computing array. Quality of a mapping intermediate state corresponding to the processing unit that each operator node maps to is quickly predicted through the pre-trained mapping quality model, the target mapping processing unit of each operator node can be determined quickly according to the quality, the quantity of search branches is decreased, data flow diaphragm mapping time is shortened, and data flow diaphragm mapping efficiency is improved.