Several aspects of the reproductive biology of the white-spotted longicorn beetle, Anoplophora malasiaca THOMSON, were observed. Seventeen pairs of adults which emerged in early- to mid-June were reared under the conditions of natural temperature and daylength. The mean length (±SD) of sexual maturation period was 9.8±1.4 days. Mean life span of adult females was 77.6±20.3 days and mean total number of eggs laid was 193.8±65.2 per female. The fecundity curve was bell-shaped with a long rightward tail, having a peak about the 30th day after emergence. Remarkable decrease of the number of eggs with seasonal fluctuation seemed to coincide with the low mean daily temperature. From changes in the number of oviposition sites and the oviposition ratios (no. of eggs/no. of oviposition sites), the temporal pattern of oviposition could be divided into four phases. Hatchability of deposited eggs ranged from 0.78 to 1.0, and the mean hatchability in the study overall was 0.9.