The invention relates to a 
hardware Trojan horse detection method and 
system based on a bidirectional graph 
convolutional neural network. The method comprises the following steps of firstly, preprocessing a 
netlist file, creating a corresponding 
directed graph representation, encoding gate device information as a feature representation X, and constructing circuit 
directed graph data, respectively creating a forward 
circuit diagram for describing a circuit 
signal propagation structure and a reverse 
circuit diagram for describing a circuit 
signal dispersion structure, respectively constructing corresponding graph neural network feature extractors to extract structural features, and combining the structural features into final gate device features, constructing a multi-layer 
perceptron classification model, forming a 
hardware Trojan horse gate classification model by the multi-layer 
perceptron classification model and a graph neural network feature extractor, and learning 
model parameters by using a weighted 
cross entropy loss function to obtain a trained 
hardware Trojan horse gate classification model, and converting a to-be-detected 
netlist into a 
directed graph, inputting the directed graph into the trained 
hardware Trojan horse gate classification model for detection, and outputting a suspicious door device 
list. According to the method, the exit-level 
hardware Trojan horse can be effectively detected.