The Fish fauna of the Hwajinpo Lake, one of the lagoons on the east coast of Korea, was investigated during six days between November,2003 and May,2004. Fifteen species belonging to eight families and six orders were collected. Among the 15 species recorded, brackish water and/or marine fishes were represented by six species, while three additional species were identified as migratory fish, and six species were purely freshwater fish. During the six months, all of the survey period with six sampling dates, nine species belonging to six families were collected at Station 1, with Chaenogobius urotaenia presenting the highest biomass (39 % ). Twelve species belonging to six families were collected at Station 2, with Carassiu cuvieri showing the highest biomass (20 % ). Five species belonged to three families at Station 3, with Hemiculter eigenmanni showing the highest biomass (69 % ). The dominant and subdominant species were C. cuvieri ( 16% ), Carassius auratus and Tribolodon hakonensis ( 14% ), respectively. Also, diversity indices were 0.95 ( Station 3) and 2.08 ( Station 2), while the dominant indices were 38.40 ( Station 2) and 87.18 ( Station 3 ). The evenness indices were calculated with 0.59 ( Station 3 ) and 0.84 ( Station 2).