Book 1ouse Liposcelis bostrychophila is a minor pest in stored products, and may seriously infest the stored prod, ucts when its population outbreaks. This study was conducted to evaluate the toxic effect of DDVP on various development stages ofL, bostrychophiha. The results showedthat at 28±0.5℃ and 24h exposure under 75%～80% RH, the LCso of the eggs, 18-rvae of 1st to 4th stadium, and adults was 16.83, 0.22, 0.22, 0.23, 0.26 and 0.25ug·L-1, respectively. The 1ethal effect of DDVP on the adults at different exposure periods showed that their mortality was linearly related to the treated time. implying that the test colony of L. bostrychophila was susceptible to DDVP. In the practical fumigation. DDVP as a fumigant had a good effect on the pest control if the development stage, time and periods of treatment were appropriate.