Wood boring insects are the major problem of many industries, such as hardwood brokers, importers, merchants, and manufacturers of furniture. Phosphine (PH3) is highly toxic to insects and is known to penetrate treated material. In this study, effectiveness of PH3 which is altered methyl bromide, was examined with Monochamus saltuaris, Platypus koryoensis, Cryphalus fulvus, and Xyleborus mutilatus. Fumigation to M. saltuaris, P. koryoensis, C. fulvus, and X. mutilatus was carried in a desiccator (12L) at 20℃ for 24 h. As a result, LC99 of PH3 to M. saltuaris, P. koryoensis, C. fulvus, and X. mutilatus was showed 0.455 mg L-1, 0.804 mg L-1, 0.243 mg L-1 and 0.046 mg L-1 in a desiccator(12L) at 20℃, respectively. M. saltuaris, P. koryoensis, C. fulvus, and X. mutilatus 100 % mortality was showed in a fumigation chamber (10 m3 and 100 m3) at normal temperature. In these results indicates that PH3 described could be useful for fumigant agent of 4 species wood pests.