Under alkaline soil conditions, the effects of fertilization on photosynthetic characteristics and yield of oil sunflower were investigated. It was shown that non⁃rectangular hyperbolic model was appropriate to simulate the net photosynthetic rate with R2 >0�99. Photosynthetic rate, stomatal conductance and transpiration rate were enhanced significantly with the increase of photosynthetically active radiation after fertilization, while intercellular CO2 concen⁃tration was constantly decreasing. For characteristic parameters of light response curves, the apparent quantum effi⁃ciency and maximum net photosynthetic rate reached the highest value under phosphorus⁃free treatment ( NK) . Dark respiration rate and light compensation point were the highest under no potassium condition ( NP) . Light saturation point, yield, biological yield and product increase ratio went maximum under full application of NPK conditions. The highest grain weight was achieved with bio⁃organic fertilizer application. Unfilled grain rate was the lowest with no po⁃tassium applied ( NP) . In conclusion, proper fertilization could increase grain weight, reduce unfilled grain rate, and increase the accumulation of photosynthetic products and production. Therefore, during the filling stage of oil sunflower, it was feasible to apply phosphorus, potassium and organic fertilizers on the basis of more nitrogen fertiliz⁃er rationally to increase the economic output based on the improvement of photosynthetic characteristics.%在碱化土壤条件下，研究了不同施肥措施对油用向日葵光合特性及产量的影响。结果表明，运用非直角双曲线模型对净光合速率进行模拟，拟合程度高（R2＞0�99）。不同施肥处理油用向日葵的净光合速率、气孔导度和蒸腾速率均随光合有效辐射的增加而明显提高，之后趋于平缓，而胞间CO2浓度持续降低。无磷（ NK）处理下，表观量子效率和最大净光合速率最大；无钾（ NP）处理下，暗呼吸速率和光补偿点均最高；氮磷钾（ NPK）全施的条件下，光饱和点、产量、生物产量和增产率均最高，千粒重以生物有机肥处理最佳，而秕粒率则以无钾肥（ NP）处理最低。从回归方程看出，施肥可以提高千粒重，降低秕粒率，增加光合产物的积累，提高产量。因此，在油用向日葵灌浆初期，在增施氮肥的基础上，合理配施磷钾肥和有机肥，可从改善其光合特征的基础上提升经济产量。
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