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Optimizing the configuration of row spacing and the dosage of 1,1-dimethyl-piperidinium chloride (DPC) in machine-picked cotton is an important means for constructing a reasonable individual and group structure for cotton and increasing yield. 'Yuanmian 11' was used as planting material and a split-plot experimental design was adopted. Under the condition of consistent density, the main plot was set with 2 plant row spacing configurations including 76 cm equal row spacing and (66+10) cm wide and narrow row spacing; the sub-plot was set with 4 doses of DPC, which were 270, 410, 550 and 690 g•hm-2, respectively. The effects of different treatments on the growth rate of the main stem of cotton, plant structure, canopy characteristics and yield components were studied. The results showed that under the same DPC treatment, 76 cm equal row spacing mode increased the daily growth rate and internode length of the main stem of cotton, increased the angle of the lower fruit branches and the length of the upper fruit branches, reduced the length of the lower fruit branches and the angle of the upper fruit branches, and had a reasonable distribution of leaf area index in the vertical direction of the canopy, which improved the number of bolls per plant, single boll weight and seed cotton yield. Under the same planting mode, the daily growth rate of the main stem of cotton, the internode length of the main stem at various parts, and the length of the first fruit internode of the upper fruit branches were all inversely proportional to the dose of DPC.The angle of fruit branches at various parts increased first and then decreased with the increase of DPC dose. Increasing the dose of DPC could reduce the leaf area index of cotton to a certain extent. Based on the comparison and analysis of cotton plant type and yield in this experiment, it was recommended that cotton with 76 cm equal row spacing configuration mode should be sprayed with 550 g•hm-2 DPC during the whole growth period, while cotton with (66+10) cm mode should be sprayed with 410 g•hm-2 DPC to obtain an ideal yield. Above results provided a theoretical basis for the selection of plant row spacing configuration and the application of chemical control management measures for machine-picked cotton in Xinjiang. [ABSTRACT FROM AUTHOR]