Abstract: Selecting wheat cultivar Jimai20 as experiment material, under short period of heat shock (35~39℃) at the middle stage of grain filling , the effects of halving spikelet on 1000-grain weight and quality of wheat grain were investigated. The results showed that 1000-grain weight, protein concentration, protein accumulation amount per grain, wet gluten content, flour development time and flour water absorption were improved comparing with the treatments of CK and Heat Shock without halving spikelet . Mixing tolerance index and time to breakdown diminished. Meanwhile, the concentration of starch and amylopectin decreased, amylose content and ratio of amylase to amylopectin increased. The breakdown value and peak viscosity of flour diminished. It was indicated that resulting from improved nitrogen supply to the remained grain by halving spikelet, the rheological properties of dough become more resistant to heat shock but the quality of starch was worsen.