Abstract: ‘Changfu 2’ apple was used as the materials, and the different dosages of seaweed compound water-soluble fertilizer were applied in the early stage of apple, conventional fertilizer was used as the control（CK）.The effects of different dosages of seaweed compound water-soluble fertilizer on apple single fruit weight, autumn shoot length, fruit quality and fruit color were studied, in order to provide reference for rational fertilization of apples.The results showed that the treatment of seaweed compound water soluble fertilizer could significantly increase the length of autumn shoot compared with CK.The autumn shoot length of HT6 treatment was the longest, which was significantly increased by 28.56% compared with CK.Under the same period of fertilization condition, the autumn shoot length of high dosage of seaweed compound water-soluble fertilizer treatmnet（HT2,HT4,HT6） were higher than the low dosage of seaweed compound water-soluble fertilizer（HT1,HT3,HT5）.Compared with CK,the titratable acid of HT6 treatment was significantly reduced by 40.74% and the solid-acid ratio was significantly increased by 70.86%.In terms of fruit color, the fruit brightness and color saturation of HT6 treatment were better than other treatments, which the color saturation of HT6 treatmnet was significantly higher than that of CK.Principal component analysis was carried out and the comprehensive score of HT6 treatment was the highest and ranked first.Comprehensive analysis showed that the treatment of HT6 had the best comprehensive effect on promoting the growth of autumn shoots and improving fruit quality and color.