Growth and age of the Surf clam, Tresus keenae (Bivalvia: Mactridae) were collected from Yeosu coast in Korea. Relative growth equations among SL, SH, SW and TW of Tresus keenae were ranged from 0.8188 to 0.9468. The ring radius were estimated from a von Bertalanffy method with the values of SL1.54 = 44.72 mm, SL2.54 = 70.97 mm, SL3.54 = 91.51 mm, SL4.54 = 107.09 mm, SL5.54 = 122.86 mm. Back calculated total weight at the formation of annual ring on the shell of Tresus keenae with the values TW1.54 = 301.99 g, TW2.54 = 467.72 g, TW3.54 = 595.14 g, TW4.54 = 690.65 g, TW5.54 = 786.58 g. Growth curves for shell height (SH) and total weight (TW) fitted to the von Bertalanffy equation were expressed follows :

SLt = 200.02(1 – e–0.1987(t + 0.14))
TWt = 1,711.93(1 – e–0.1987(t + 0.14))2.8225