The synchronization of biological neural networks plays an important role in the information processing of brain. In this paper, the dendritic-integration effect in Hodgkin-Huxley neuronal network was considered to obtain a modified DHH (Dendritic-integration-rule-based HH) neuronal network model,and the firing and synchronization characteristics of the network were studied. Firstly,taking a coupled system of three inhibitory neurons as an example,it is found that the dendriticintegration effect enhances the firing threshold of neurons. Then a globally coupled inhibitory neuronal network and a globally coupled excitatory neuronal network were established, respectively,which show that large coupling strength not only induce the networks to achieve nearly complete synchronization but also greatly affect the firing amplitudes of the networks. Interestingly,when the integration coefficient is set to be a certain value,the inhibitory neuronal network achieves the highest extent of synchronization,while the excitatory neuronal network achieves the lowest extent of synchronization.