Low temperature dehydration process was used to produce solid amino acid water soluble fertilizer additive with tail liquid of amino acid fermentation，and amino acid water-soluble fertilizer was prepared by mixing this synergistic substances with ordinary water-soluble fertilizer. A field experiment was conducted to study the effects of amino acid water soluble fertilizer on the growth of tomato. There was four treatments in the experiment，including the conventional water soluble fertilizer treatment(CF)，amino acid water solution treatment with equivalent NPK(AF)，conventional water soluble fertilizer with 20% reduction in NPK(4/5CF)，and amino acid water solution with 20% reduction in NPK(4/5AF). Compared with CF treatment，the yield of AF，4/5CF，4/5AF treatment increased by 11.23%，-3.59%，2.62%，respectively. Amino acid water soluble fertilizer significantly improved the quality of tomato fruit，and the content of soluble sugar and vitamin C content was most increased obviously by an average of membership function method. Compared with CF treatment，sugar and vitamin C contents were increased by 29.4% and 8.25%，respectively，economic benefits of AF and 4/5 AF treatments were 52533.0 and 12049.5 yuan/hm²，respectively. Amino acid water soluble fertilizer with NPK reduced by 20% could ensure better yield and fruit quality than those of the common water soluble fertilizer.