Objective To investigate the popularity and distribution of Paragonimus westermani in Nankun Mountain,Northern suburban of Guangzhou.Methods 2012 snails and 63 crabs were picked from creeks.Three feces samples of wild cats in epidemic area and two feces samples of domestic cats inoculated with P.westermani metacercariae were collected.The cercariae,metacercariae and eggs of P.westermani were detected.P.westermani-positive cats were identified by detection,in which adults of Paragonimus were checked.P.westermani eggs artificially inoculated were also anatomized.Results Infection ratio in snails was 0.15‰(3/2000),while infection ratio of P.westermani metacercariae in crab was 100%(59/59),with an intensity of infection of 2~516 metacercariae per crab,and 2~10 matacercariae per gram crab.Snails and crabs were identified to be Semisulcospira libertina type and Sinopotamon pinheense type,respectively.P.westermani eggs were also found in two feces samples from wild cats,with an infection ratio of 66.66%(2/3).Eleven adults of P.westermani were found in two domestic cats inoculated with P.westermani.Conclusion Nankun Mountain in northern suburban of Guangzhou as an ultra-high infectious focus of P.westermani(Grade I) is reported for the first time.In view of the fact that P.westermani is one of the major disease paragonimus and the infectious focus Nankun Mountain nature reserve is an 4 A scenic spot and popular summer resort,tourists can become infected by P.westermani by drinking water from streams,springs and ponds.More attention should be paid to prevent human infection with P.westermani in Nankun Mountain.