This paper estimates an aggregate stochastic production frontier using time-series data for the Korean economy in 1973-2007 to examine whether public capital stock reduces aggregate technical inefficiency in the gross domestic product and also introduces an average production function to measure output elasticity of public capital. A stochastic production frontier is estimated in first-differenced form, and the one-sided residuals are regressed against the stock of public capital per labor. First of all, this paper shows that the value of estimated elasticity of public capital stock is positively low and is insignificantly different from zero. This result contrasts with the widely reported previous empirical result that public capital increases real output in the Korean economy as a direct input in an average production function. This result also reveals that estimated technical inefficiency is negatively related to public capital and suggests that public capital stock reduces technica