Abstract: Artificial neural network which can stimulate the structure and function of the human brain is a kind of information processing system.The hardware realization of artificial neural network can make full use of the characteristics of large scale parallel processing of the neural network and promote the further development of the basic research of brain science.In this study,Integrate-and-Fire (IF) neuronal circuit was designed;the Spike-Timing Dependent Plasticity (STDP) mechanism was designed;the neuronal connection circuit based on STDP mechanism was built;the effects of STDP mechanism on the discharge characteristics of the neuronal circuit were analyzed.The result shows that:in the neuronal circuit based on the STDP mechanism,the synaptic weights will change and further affect the pulse release of the post-synaptic neurons when the pulse spike of the pre-synaptic and post-synaptic neuron has the time difference.