In order to provide theoretical basis for rational utilization of cow manure compost and vermicompost，improve phosphorus utilization efficiency of livestock manure and reduce phosphorus pollution，biochemical characteristics of phosphorus in cow manure compost and vermicompost were evaluated. In this study，amplicon sequencing technology was used to study the differences in phosphorus content，phosphatase activity and P-solubilizing microorganisms in cow manure compost and vermicompost. Compared with cow manure compost，pH，electrical conductivity，the contents of available P，total carbon and total nitrogen，C/P and N/P in vermicompost decreased significantly，and pH decreased by 0.46，and electrical conductivity，the contents of available P，total carbon and total nitrogen decreased by 63.86%，20.99%，28.51% and 45.57%，respectively. The C/P and N/P of cow manure compost were 4.20 and 5.52 times that of vermicompost，respectively. However，the total P content and C/N of vermicompost increased significantly，the total P content increased by 196.40%，and the C/N ratio was 1.31 times that of cow manure compost. Alkaline phosphatase activity in vermicompost was lower than that in cow manure compost，while there was no significant difference in acid phosphatase between them. The α-diversity of bacteria and fungi in vermicompost was significantly higher than that in cow manure compost. The relative abundance of Arthrobacter and Bacillus in vermicompost was significantly lower than that in cow manure compost；on the contrary，the abundances of other P-solubilizing bacteria and most P-solubilizing fungi were higher than those in cow manure compost. The attenuation effect of vermicomposting on available P content mainly depends on the chemical properties of cow manure compost and the abundance of P-solubilizing microorganisms.