To investigate tick species and prevalence of Anaplasmataceae and spotted fever group Rickettsia(SFGR)in ticks collected from sheep and goats in Leibo county,Sichuan Province.Ticks were preliminary identified by morphological characters and the genomic DNAs of ticks were ex-tracted.Molecular detection was performed by PCR targeting gene fragment of tick ITS-2,gltA and ompA genes of Rickettsia spp.,16S rRNA and rpoB genes of Anaplasma spp.and Ehrlichia spp.Positive PCR products were sequenced and phylogenetic trees were built based on these genes.The results showed that a total of 353 adult ticks collected from sheep and goats were identified as H.longicornis.The total prevalence of SFGR in H.longicornis was 22.66％(80/353)with only R.raoultii detected,which was closely related to R.raoultii(JQ792163)isolated from Dermacentor niveus in Tibet.The total prevalence of Anaplasmataceae was 87.82％(310/353)with six Ana-plasma species(A.bovis,A.capra,A.marginale,Anaplasma cf.marginale,Anaplasma sp.,Can-didatus A.mediterraneum)and two Ehrlichia species(E.chaffeensis and Ehrlichia sp.)detec-ted.Go-infection was found in some H.longicornis as high as 7.37％(26/353).The results indica-ted that H.longicornis may be the dominant tick species in Leibo county with high infections rates of Anaplasmataceae and SFGR.The close monitoring of the tick-borne pathogens should be strengthened in the future research work.