The taxonomic study on the Caprellidea collected from the shallow waters of north-west area of Mirs Bay, Hong Kong revealed the distribution of four species in this area. Of them, Tropicaprella minuta, new genus, new species, and Caprella hirayamai, new species, are described. Tropicaprella, new genus, is close to Heterocaprella Arimoto, 1976, but differs by the absence of the clavate projection on the pereonite 4, the elongate pereopods 3 and 4 and the five-articulate pereopod 5. The closest species to Caprella hirayamai, n. sp., are Caprella californica Stimpson, 1857, and Caprella scaura Templeton, 1836, but C. hirayamai can be easily distinguished by less elongated pereonite 1, short basis of gnathopod 2 and oval propodus with dorsal setae in gnathopod 2.