Many studies on the crop response to climate change have been examined for isolated plnts or plants grown in a small-scale popuration. We constructed a Temperature Gradient Chamber(TGC) in a lowland field of Okayama University to clarify the effect of rising temperature on growth, yield and dry-matter production of winter wheat during the whole growth season. The four experimental plots were arranged by the distance from the intake side, TGI(control), TG2, TG3, and TG4. The temperature gradient occurred from TG1 to TG4, the daily ,mean temperature in TG4 increased 2.8℃ more than that of TG1. The dry weight in hight-temperature plots was larger than TG1. The grain yield per M2 was lowest in TG1(218g) and highest in TG2(248g), but gradually decreased with resing temperature in TG3(230g) and TG4(225g). The percentage og spikelet sterility and floret sterillity were not significantly different among the plots. The grain yield tended to decrease with higher the temperature more than 28℃ during the ripening period due to the decrease in dry-matter accumulation in the panicle at the latter ripening period. Clearly, rising temperature increased the wheat grain yield until 28℃ of daily mean temperature during the ripening period, furtuer rise in temperature limited the yild due to the decline in photosynthetic activity.