Disclosed is a separator for female and male mosquito pupae, comprising a fixed plate (2) arranged on an inclined base plate (1), and an adjustment plate (3) spaced apart from the fixed plate (2) with the gap gradually narrowing from top to bottom, wherein gap adjustment members are respectively arranged from the upper and lower parts of the fixed plate (2) to the corresponding positions on the adjustment plate (3), and a flow guide plate (8) is arranged below an outlet of the gap between the fixed plate (2) and the adjustment plate (3). The separator has a simple and rational structure, and can sequentially separate and collect the larvae, male pupae and female pupae of mosquitoes according to different chest widths, and has a simple operation, fast separation speed and good separation effect.