Disclosed in the invention is a plant growth-regulator containing 6-benzylaminopurine, and the present invention in particular relates to a water-soluble composition containing 6-benzylaminopurine and a preparation thereof the plant growth-regulating composition comprises the following components with the following weight ratios: A. 0.05-5 parts of 6-benzylaminopurine B. 10-30 parts of at least one alkaline ingredient selected from tripotassium phosphate, trisodium phosphate, dipotassium hydrogen phosphate, disodium hydrogen phosphate, potassium tripolyphosphate, sodium tripolyphosphate, disodium octaborate tetrahydrate, potassium tetraborate, borax, triethanolamine and ethanolamine and C. 5-30 parts of at least one chelating agent ingredient selected from disodium EDTA, calcium EDTA, magnesium EDTA, calcium disodium EDTA, magnesium disodium EDTA, sodium citrate and potassium citrate the present invention can effectively improve the solubility property of 6-benzylaminopurine in water, and improve the efficacy thereof furthermore, the plant growth-regulating composition containing 6-benzylaminopurine of the present invention can also avoid the adverse effects on the health of the human body caused by using a strong acid or alkali.Linvention concerne un régulateur de croissance végétale contenant de la 6-benzylaminopurine, et en particulier une composition hydrosoluble contenant de la 6-benzylaminopurine et sa préparation. La composition contenant le régulateur de croissance comprend les composants suivants dans les proportions pondérales suivantes : A. 0,05 à 5 parties de 6-benzylaminopurine B. 10 à 30 parties dau moins un ingrédient alcalin choisi parmi le phosphate tripotassique, le phosphate trisodique, le phosphate dipotassique dhydrogène, le phosphate disodique dhydrogène, le tripolyphosphate de potassium, le tripolyphosphate de sodium, le tétrahydrate disodique doctaborate, le tétraborate de potassium, le borax, la triéthanolamine et léthanolamine et C. 5 à 30
