A study on the biology of a carsidarid, Tenaphalara malayensis Crawf, a pest of durian, was carried out at Universiti Pertanian Malaysia, Serdang. In the glasshouse (31 ±7°C and 70 ± 30% RH) the insects life cycle (egg-adult) was completed in 19 days with a 7-day preoviposition period. There were altogether five nymphal instras. Eggs were laid singly hidden in the slits made beneath the scales on the underside of the bud leaf The egg incubation period was 3 days. The duration of the first, second, third, fourth and fifth nymphal instars were 3, 3, 3, 3 and 4 days, respectively. The average fecundity of the female carsidarid was 50 eggs. The longevity of the adult male and female were 9 and 12 days, respectively. The female life-table analysis produced a net reproductive rate (R J value of 3.35, the finite capacity for increase (r J value of 1.11 and the generation time (T) of 27 days.