To analyze the influence of site factors and stand factors on the occurrence of Pissodes nitidus and the damage caused by Pissodes nitidus, the site factors，stand factors and the damage caused by Pissodes nitidus in 177 sample plots(with 24 compartments，59 sub-compartments)in broad-leaved Korean pine mixed forest were investigated，and the percentage of insect-infected trees, population density, Simpson diversity index were calculated. The result showed that the damage of P. nitidus on broad-leaved Korean pine mixed forest at the south slope was more serious than that in the north slope and the disease incidence of the south slope was 189.80% as much as that of the north slope. The disease incidence of the south slope accounts for 52.54% of the total samples, thus the south slop is the main morbidity region. When the percentage of insect-infected trees in the damaged area and the canopy density were fitted , the equation y = –12.689x2 – 11.713x + 27.843 was obtained，and the correlation coefficient R2=0.666 4. When the percentage of insect-infected trees in the damaged area and Simpson diversity index were fitted, the equation y = 0.001 3x2 – 0.060 4x + 1.084 1 was obtained，and the correlation coefficient R2=0.720 8. The results indicated that with the increase of the Simpson diversity index and canopy density, the infection rate of pests was obviously decreased. The P. nitidus population density is significantly correlated with the average tree height and diameter at breast height of the arbor.