Effects of S-3307(Uniconazole) application on amount to content of protein components and processing quality of wheat grain were studied in more rain and low light stress environment.The results showed that increase application of S-3307 significantly improved content of protein components by different extent.Rations of albumin and globulin to total protein increased significantly,about which B2 was the best,and rations of gliadin and glutein increased with the increase of concentration.Application of S-3307 significantly increased WGC and SDS,prolonged DDT and DST,and improved its WA,increased VV,and subsequently improved the processing quality of wheat grains.