This paper applies the discrete-choice model technique of analyzing differentiated product markets to the equilibrium of Korean fertilizer market. The supply and demand for 378 different brands of fertilizers are empirically analyzed. The impacts of the several characteristics of the brands on market prices are estimated, and the results are compared with those from the usual hedonic price approach. The mark-up of each brand and the corresponding product-level demand elasticity are also estimated. The average estimated markup is about 69%, which implies that the brands are substantially differentiated from one another.