| A field experiment was conducted to determine the regulation of crop photosynthesis and output and water saving effect under ridge and furrow rain harvesting with supplemental irrigation in Guanzhong irrigation district. We studied the effects of photosynthetic rate, chlorophyll fluorescence parameters and yield of winter wheat. The results showed that Pn of ridge and furrow rain harvesting which were 57.1%～84.4% and 25.3%～50.3% higher than that of CK and border irrigation, Fm、Fv、Fv/Fm、Fv/Fo、qP and yield of each ridge and furrow rain harvesting treatments were also higher than that of flat planting, but qN was opposite. Both two width of ridge and furrow rain harvesting treatments boosted grain yield by 74.6%～124.9% compared with CK, ridge and furrow rain harvesting with supplemental irrigation treatments enhanced grain yield compared with border irrigation by 0.3%～18.9%, the higher irrigation amount the higher yield, and the wide furrow was better than the narrow one. Therefore, in the year of less rainfall, efficiency of light energy conversion increased by 44.1% under 60 cm rain harvesting cultivation. It is concluded that ridge and furrow rainfall harvesting could improve the efficiency of light energy conversion and the quantum yield, improve the efficiency of photosynthesis and maintain higher grain yield under the conditions of half supplemental irrigation amount of border irrigation. |