The authors reared the ash-gray leaf bug, Piesma maculata in the growth cabinet controlled as temperature groups of $15, 20, 25, 30, 40^{\circ}C$under condition of photoperiod 16L:8D, light intensity $510{\pm}240$ lus, relative humidity $65{\pm}3%$, and analyzed the effects of temperature on the development of the insect. The results are summarized as follow: There are highly significant differences the developmental periods for the temperature groups, and between the developmental periods for the developmental stages. The egg in the temperature of 15 and $40^{\circ}C$ was hatched, but the ecdysis was impossible. The thermal threshold was $12.34^{\circ}C$and the upper lethal temperature $40.39^{\circ}C$. The total developmental periods of egg to adulate in the temperature of 20, 25, 30 and $35^{\circ}C$are 40.52, 22.37, 15.91 and 13.00 days, respectively. That is, the developmental period was decreased, as the temperature was increased. In the developmental period for the developmental stages, the developmental period of egg stage was longer than that of 25, 30 and $35^{\circ}C$, and that of 25。C was longer than that of $35^{\circ}C$. But ther was not significant differences between the developmental periods for the other temperature group. The rate of hatch at$20^{\circ}C$is the greater value as 90%, and the rates of 25, 30 and $35^{\circ}C$ are 79, 79 and 67%, respectively. That is the rate of hatch was decreased, as the temperature was increased. The mortality in the temperature of $35^{\circ}C$ is the greatest value as 68%, and those of 30, 25 and $20^{\circ}C$are 59, 59 and 41%, respectively. That is, the mortality was increased, as the temperature was increased. There was not significantly differences between the developmental period of female and male.