To understand how the yield of irrigated winter wheat in Northern Xinjiang might be affected by climate warming,a set of manipulative experiments was conducted in QiTai by using the technique of Free Air Temperature Increase(FATI)in the field.Three warming treatments(T_(12):night warming;T_(24):all-day warming;CK:control)were applied from setting stage to maturity.The results show that warming affect the growth and the yield of winter wheat through changing the photosynthetic characteristics and the growth index,like leaf area,plant height,dry matter partitioning. The yield decreased by 1.7% with all-day warming treatment,while decreased 18.9%significantly with night warming.Our findings are consistent with some of previous reports of yield decreases with warming.The result showed that warming would cause premature senescence of functional leaves of winter wheat,would reduce the transport of photosynthetic products to ear,which was not conducive to yield formation.