The life history and biological characteristics of the population of leaf beetles, Colaphellus bowringi Baly, on the host plant Brassica kinensis in Harbin were reported. The results showed that most individuals occurred 1 generation per year, but a few individuals had 2 generations per year. The beetles hibernated as adult in the soil. The diapaused adults burrowed in soil to depths of 2～27 cm. The adults began to appear from the soil inthe late April. The first generation occurred from early May to early July. About 11 (±1.49) % of the first generation adults reproduced and the others entered diapause. The second generation occurred from mid_June to mid_July. All adults beetles entered in soil to hibernate at the end of July. The oviposition period of the overwintered generation was 6～55 d with the average of 30.95 d. The female could produce 454.9 eggs on average. At 25℃, developmental duration was (4.46±0.33) d in the egg stage, (8.22±0.26) d in the larval stage, and (4.17±0.22) d in the pupal stage. Developmental threshold temperature was 10.80℃ for eggs, 10.95℃ for larvae and 9.79℃ for pupae. The effective accumulative mperature was 64.82 day-degrees for eggs, 117.31 day-degrees for larvae, and 64.36 day-degrees for pupae.

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