A systematic analysis and optimizing design have been conducted for the integration of Si 1-x Ge x optical waveguide and Si 1-x Ge x/Si multiple quantum wells (MQW) infrared detector at λ=1.55 μm operation. The optimizing design results are: (1) For Si 1-x Ge x optical waveguide, Ge content x=0.05. Rib width, height and etched depth of the waveguide are 8, 3 and 2.6 μm, respectively; (2) For Si 1-x Ge x/Si MQW infrared detector, Ge content x=0.5. Total thickness of the detector is 550 nm, which consists of 23 periods 6 nm Si 0.5 Ge 0.5 +17 nm Si. The length of the detector is about 2 mm. The results show that the internal quantum efficiency of such structure devices can be as higher as 88%.