Temperature is one of the important factors affecting the rice’s growth and development, but little is known about the impact of nighttime temperature increase on the yield of double season rice. Different nighttime temperatures in two glass-houses were established to investigate the effects of nighttime temperature increase on the yield of double season rice. For early season rice, the grain yield decreased by 5.42%-9.48% with each 1℃ increase in growing-season minimum temperature. With such a nighttime temperature change, the grain yield of late season rice was promoted by 8.99%-1128%. The nighttime temperature increase facilitated the tillering of both early and late rice, increased the effective panicles, but inhibited spikelets differentiation. Moreover, the rise in nighttime temperature reduced the filled grain rate of early rice, but improved the filled grain rate of late rice.