Using transfer matrix,the gain effect of optical propagation properties in optical quantum well for complex medium be studied.The result shows that,in optical quantum well,the transmissivity or internal local electric can be activated by complex medium:Whether optical quantum well from real medium or complex medium,there have a strong internal local electric field in the well,and appear discrete transmission spectrum them from the frequency quantization.Impurity activation be add to complex medium A,when the k which is the permittivity of imaginary part is positive number,the local electric field and transmission all be weakened,and the k increase the decay more faster,but for different wave length,internal local electric field response to the k is different,it is fastest in the center wavelength.when the k which is the permittivity of imaginary part is positive number,the local electric field and transmission all to implement optical gains,but with the k increase internal local electric field increase to a maximum,and then be weakened.For different wavelength,internal local electric field response to the k is different;it is fastest in the short-wavelength,and slowest in the long-wavelength.Modulation of optical propagation properties in optical quantum well by complex medium can provide guidance for research and design optical filter,optical amplifier or all-mirror optics,and help to study the optical transmit characteristics in the internal local electric field.