介绍了青岛胶州湾湾口海底隧道的工程概况并采用软件flac3D对隧道开挖和支护进行了两种方案的二维数值模拟。通过分析隧道周边关键点位移和围岩塑性区，研究了小间距海底隧道开挖支护过程对各条隧道围岩稳定性的影响，得出了有益于设计和施工的结论和建议。

The subsea tunnels located at Jiaozhou Bay in Qingdao is presented in this paper. Twodimensional numerical simulation of two schemes is performed using flac3D. The displacements at the key points in the tunnel and the plastic zones in the soil are analyzed to study the effects on the stability of surrounding ground induced by the constructions of parallel adjacent subsea tunnels. And some conclusions and suggestions which can help design and construction are given finally.