The invention discloses a method for rapidly separating and detecting mixed explosives and belongs to the detection technologies of trace mixed explosives. According to the method, the physical characteristics that different explosives have different melting points and boiling points are utilized, an electric heating technology is adopted, and phased continuous temperature rise control is adopted near the melting points or the boiling points, the detection for the mixed explosives is finished in a wider temperature range, and the method is simple in principle and easy to realize. After the technology is mature, a novel light mixed explosive product detector can be formed, has the characteristics of small size, light weight, low cost and portability in use, and can be flexibly used for rapidly detecting various mixed explosives in public places.