The growth and production of Aulichthys japonicus (6.70∼15.32 cm TL) were investigated in an eelgrass bed of Dongdae Bay, Korea throughout 2006. A total 888 A. japonicus were collected with a small beam trawl. Growth in fish total length was expressed by the von Bertalanffy's growth equation as: L_t=24.8257(1-e^{-0.5583(t+0.4816)}). The densities, biomass, daily, annual production, and P/B ratio were 0.01±0.009/m^-2, 0.17±0.16g/m², 0.00006±0.00006g AFDW/m²/day, 0.02g AFDW/m²/yr, and 0.12, respectively. Monthly variation in production of A. japonicus was large; the peak occurred at July, September and November 2006 (0.000182, 0.000127 and 0.000123g AFDW/m²/day), where as the lowest value was 0.000003g AFDW/m²/day at April and May 2006. Monthly change in production of A. japonicus was positive correlated with number of individuals, biomass and growth rate.