Abstract: This paper reports on the discovery of cercariae which are similar to those of Echino-tomatidae in Melanoides tuberculata in Yunxiao and Zhaoan Counties of Fujian. Encysted metacercariae were found in the gills of fresh-water fish after experimental infection with the cercariae for 3 to 4 hours. Adult worms identified as Echinochasmus japonicus were obtained front Mesocricetus auratus and dove after infection with the metacercariae. Melanoides tuberculata was recorded for the first time as the first intermediate host of E. japonicus and its natural infection rate was found to be 1.1%. The morphological characteristics of the cercaria are described.