Objective To analyze the changes in the amino acid composition and content of Eriobotryae folium in the twelve months,and to can provide a theoretical basis for the harvesting period and resource utilization of Eriobotryae folium.Methods The amino acid composition and content of Eriobotryae folium in different months were determined by high performance liquid chromatography with phenyl isothiocyanate pre-column derivation.SPSS22.0 software was used to analyze the statistical significance difference and data correlation.According to the ideal model proposed by the World Health Organization(WHO)and the Food and Agriculture Organization of the United Nations(FAO)and the amino acid ratio coefficient method proposed by Shengtao Zhu,the amino acids of Eriobotryae folium at different harvest periods were scored.Results There were seventeen kinds of amino acids,including seven essential amino acids(EAA),nine kinds of children's essential amino acids(CEAA),and nine kinds of medicinal amino acids in Eriobotryae folium at different harvesting periods.The seventeen amino acids were aspartic acid,glutamic acid,serine,glycine,histidine,arginine,threonine,alanine,proline,tyrosine,valine,methionine,cystine,isoleucine,leucine,phenylalanine,and lysine;and the average contents were 3.41-7.23,4.64-9.66,2.05-3.75,2.99-4.95,0.01-1.56,2.33-4.85,2.10-4.03,2.67-5.48,5.37-7.64,1.45-3.49,2.70-5.53,0.01-0.48,3.64-4.78,1.91-4.15,3.96-7.83,2.39-4.60,1.85-3.65 mg·g-1,respectively.There were significant differences in the contents of seventeen kinds of amino acids,total amino acids,total essential amino acids,total essential amino acids for children,medicinal amino acids,and bitter amino acids in Eriobotryae folium at different harvesting stages(P＜0.05).The content of bitter amino acids in total amino acids was stable,and there was no significant difference.The content of essential amino acids was from 44.26%to 50.33%in Eriobotryae folium at different harvesting periods,significantly higher than the WHO/FAO model value(35.00%).The mean values of EAA/NEAA(55.67%)and EAA/TFAA(35.74%)were close to 60%and 40%of the WHO/FAO model values,respectively.The highest content of seventeen kinds of amino acids in Eriobotryae folium was found in July and followed in November.SRC values ranged from 62.53 to 76.17;the highest value was November,the second was August,and the third was July.Lysine was the first limiting amino acid in Eriobotryae folium.Bitter amino acids were positively correlated with medicinal and total amino acids(P＜0.01).Conclusions The amino acids in Eriobotryae folium have a complete variety,reasonable composition,and good development and utilization value.The contents of amino acids in different months varied greatly.July and November were the optimal periods for the rational development and utilization of amino acids in Eriobotryae folium.