This study aimed at isolating plant growth promotion strains of Trichoderma strains from the tropical soil，and evaluating the effect of developed bio-organic fertilizer based on these isolated strain on yield and quality of mango.Trichoderma strains were preliminarily screened according to the growth ability at different temperature sets using series-dilution plate counting method.Then bio-organic fertilizer was developed using the strains to re-screen plant growth promotion effect on cucumber as model crop in greenhouse.The effect of bio-organic fertilizer containing the Trichoderma strain with best plant growth promotion ability in greenhouse on mango yield and quality was evaluated under field condition.Finally，the taxonomic classification of tested strain showing best plant growth promotion effect was then identified by ITS and tef1 sequence analysis.The results showed that among candidate strains of Trichoderma spp.isolated from the soil from mango orchard in Hainan，the strain MD30 showed the best growth ability at 35℃ and 40℃，respectively.The results of pot experiments showed that the bio-organic fertilizer made from strain MD30 was superior to other Trichoderma strains in promoting cucumber seedling growth.The fresh and dry weight of shoot increased by 29% and 64% in the first season，and by 116% and 53% in the second season，compared to CK.Combined with ITS and tef1 sequence analysis，MD30 strain was identified as Trichoderma longibrachiatum.The results of field experiment displayed that the yield of treatment(MD30)applied with bio-organic fertilizer developing from MD30 was significantly higher than that in CK，CF，OF and treatment(4742)applied with bio-organic fertilizer developing from NJAU4742 bio-organic fertilizer，which increased by 13%，7%，6% and 3% respectively.Moreover，MD30 treatment significantly increased the weight of single fruit，the fruit number per plant，and the contents of soluble solids，reducing sugar of mango compared with other treatments，and increased by 25%，22%，7% and 6%，respectively，compared with 4742 treatment.Therefore，the isolated Trichoderma strain MD30 could promote the yield and quality of mango in the field effectively and has a significant promoting effect on the growth of plants.