The progress of embryonic development may be observed in eggs of the rice stink bug, Oebalus pugnax (F.) (Hemiptera: Pentatomidae), because obvious color or color pattern changes may be viewed through the transparent chorion. All viable egg masses of the rice stink bug progressed through similar color or color pattern changes at the six constant temperatures that ranged from 21.1 to 37.8°C. Whenever the length of time within a pattern was expressed as a percentage of the total developmental time, the proportion of time within a pattern was not influenced by changes in temperature. However, temperatures used in this study were within the linear range for total development and within each color pattern of the rice stink bug eggs described in this article. The upper lethal constant temperature was estimated to be 37.8°C. Although phases of blastokinesis could be viewed, most were not related to color patterns in this study, except the katatrepsis phase, which is pictorially described. Rice stink bug egg masses consisted of two rows, the eggs being in contact but those of one row alternate in position with the other row. Embryos in both rows were oriented with the ventral surface toward the center of the egg mass.