The research into the impersonality and information of the Traditional Chinese-medicine Diagnosis (TCMD) is a key work to realize the Traditional Chinese-medicine (TCM) medicine examination system. So the paper studies the application of Artificial Neural Networks (NN) to TCM and uses the Genetic Algorithm (GA) to optimize the ANN, which is used to the diagnosis of TCM. The initial structure of the ANN is arbitrary and the GA is able to find a near optimal connection weight and structure of the ANN for the TCMD. In this paper, we emphatically describe t the GA to optimal the connection weight of the NN - Genetic NN, which has a relatively fixed three-layer and was used to the TCM eight principal syndromes by the tongue feature