The objective of this study is to investigate the effects of commercial organic fertilizer replacing partial chemical fertilizer on soil nutrients, plant development, and yield in cotton, and to assess the feasibility of achieving stable yield by reducing chemical fertilizer, thus providing theoretical basis and technical support for scientific fertilization and soil nutrient improvement in Yellow River Basin. A three-year field experiment from 2016 to 2018 was carried out using variety K836 with five treatments including no fertilizer (NF), traditional chemical fertilizer (NPK), commercial organic fertilizer (COF), traditional chemical fertilizer plus commercial organic fertilizer (NPK+COF), and traditional chemical fertilizer reduction 30% plus commercial organic fertilizer (0.70NPK+COF) by a randomized blocks design at Linqing city of Shandong province. Results showed that 0.70NPK+COF increased soil nutrients, dry matter accumulation, leaf SPAD value, and LAI at different growth stages in cotton, and compared with NF, the yields were annually increased by 9.63%, 26.18%, and 59.96% during three years. Compared with NPK, 0.70NPK+COF increased soil organic matter, but there was no significant difference in alkaline hydrolysis nitrogen, available phosphorus, and potassium contents of soil, dry matter accumulation, leaf SPAD value, LAI, yield and yield components between 0.70NPK+COF and NPK. Both 0.70NPK+COF and NPK had similar yield of 3976–4105 kg hm-2 from 2016 to 2018; COF+NPK increased soil organic matter, LAI, and leaf SPAD value, but there was not significantly increase in yield and yield components compared with NPK and 0.70NPK+COF. In conclusion, replacing partial chemical fertilizer with commercial organic fertilizer (0.70NPK+COF) was an economic, environmental, and feasible fertilization method for increasing soil nutrients, promoting cotton growth, maintaining high and stable yield.