The advantages of silicon photonic integration continue to be highlighted in the field of high speed optoelectronics,which are widely applied in various communication scenarios.In the development of silicon based photonic integration technology,a typical technical difficulty is the coupling of silicon waveguides and single mode optical fibers.In this paper,a silicon microlens structure integrated at the edge of the silicon on insulator(SOI)waveguide is designed.The result of BPM(Beam Propagation Method)numerical simulation shows that the designed micro lens structure can achieve 90% near field coupling efficiency between a 3μmthick SOI waveguide and a 8.6μmcore diameter single mode fiber,with the advantages of high integration,high coupling efficiency,and multi scene applicability.