In order to clarify the effect of new plant growth regulator CGR_3-1 on mungbean growth,a comparative study was conducted to study the effect of 100 mg/L CGR_3-1 on mungbean photosynthetic gas exchange parameters,photosynthate,yield and fatty acid composition by using Lüfeng 2 and Lüfeng 5 as test materials.The results indicated that CGR_3-1 made no significant effects on photosynthetic gas exchange parameters at late seed-filling stage when sprayed at the third trifoliolate stage(V3).Applying CGR_3-1 at early blooming stage(R1) significantly decreased the net photosynthetic rate of Lüfeng 2 at late seed-filling stage compared to distilled water treatment(CK) by 27.10%.In terms of photosynthate,CGR_3-1 promoted the Lüfeng 2 sucrose and starch contents in flowering stage when applied at V3 stage,which increased by 54.68% and 62.10% compared to CK group,respectively.The application of CGR_3-1 significantly decreased the Lüfeng 5 sucrose content at late seed-filling stage,however,the starch content increased.Applying CGR_3-1 at R1 stage had no significant impact on sucrose content,however,the contents of starch in Lüfeng 2 and Lüfeng 5 decreased by 22.00% and 15.53% compared to CK group,respectively.The effects of two spraying stages on 100-grain weight were different. Spraying at V3 stage decreased the 100-grain weight,however,it was increased when sprayed at R1 stage.CGR_3-1 application at V3 stage improved the number of pods and grains,and increased the yield.In addition,the plant growth regulator changed the mungbean fatty acid composition.Applying CGR_3-1 at V3 stage was beneficial to the improvement of linoleic acid.Collectively,the application of CGR_3-1 at V3 stage increased the mungbean yield per plant and improved the quality.