An important concern in further opening of Korean agricultural markets is farm income stabilization. This paper examines the fluctuations in farm income caused by the IMF financial crisis and the farm household distribution classified by the degree of the fluctuation. A newly-defined mean-variance analysis method is applied to determine the degree of increases and decreases in farm income from 1998 to 2002. The individual farm households face the different shapes of the income fluctuation. The same method is applied to analyze agricultural income. The result shows that the number of farms having a lower agricultural income compared with income in 1998 is greater than farm income. These findings imply that agricultural income will be substantially influenced by further market opening and that policies targeting income stabilization are necessary in Korean agriculture.