Abstract: To design high-quality optical filters and optical switches,the effect of double negative medium on the transmission spectrum of one-dimensional photonic crystal quantum well (AB)m(CBAABC)n(BA)m was studied with transfer matrix method. The results show that when layer C is double positive medium, there are 2n+1 narrow transmission peaks in the spectrum. While layer C is negative medium, there are only 2n-1 narrow transmission peaks in the spectrum, presenting degeneration. When the negative value of refractive index of double negative medium in layer C increases, the spectrum moves towards two sides of the forbidden band center and the quality factor of the transmission peaks improves quickly. When the negative value of optical thickness of double negative medium in layer C decreases, the spectrum draws close to the center of the forbidden band and the quality factor of the transmission peaks also speedily improves. The effect of the transmission quality factor of optical crystal quantum well on the optical thickness of double negative medium is more sensitive than the one on the negative value of refractive index. The law, the effect of the double negative medium on the characteristics of transmission spectrum in the optical crystal quantum well, can provide reference for optical crystal theoretical research and designing new quantum optical devices.