The purpose of this paper is to evaluate impacts of ENSO on frequency and spatial distribution of
rainfall in South Korea. In this paper, First, rainfall data in 60 climate stations were categorized into Warm(El
Nino), Cold(La Nina), Normal episodes based on the Cold & Warm Episodes by Season, then 100 years of daily
rainfall data were generated for each episodic events(El Nino, La Nina, Normal) using Markov Chain model.
Finally, Estimating frequency based flood and comparison for each episodes were conducted. From the results, it
shows that there are significant changes in the rainfall frequency and the spatial distribution of rainfall among
Warm(EL Nino), Cold(La Nina) and Normal episodes.