This paper tests whether exogenous shocks including agricultural policies, trade liberalization and financial crisis have impacts on the structural changes in the farm and farm household income. Unlike previous studies that specify break points prior to the estimation of regression, this paper estimates break points by fitting time series models. Tests for the structural breaks show that there is no structural break in the real farm household income whereas real farm income has five break points. Especially the break at 1997 can be interpreted as the impacts of financial crisis. The break points of 1983, 1987 and 1992 approximately match with the timings when agricultural policies that aimed better structure of agriculture and rural area were implemented. The assessed impacts of exogenous shocks at 1970, 1983, 1987 and 1992 are all positive, whereas the assessed impact of the shock at 1997 is negative. The impacts of the shock at 1997 on real farm income are assessed within the range between -1,141,432 won and -3,167,804 won.