In this study, we investigated the influence of climatic factors on rice yields across different growth stages and predicted future rice yields in different regions of South Korea. The results revealed that although climatic factors had limited effects during the vegetative growth stage, significant correlations were observed during the reproductive growth and ripening stages, with distinct positive, negative, and positive relationships between rice yield and daily temperature range, precipitation, and duration of sunshine, respectively. Multiple regression analysis of climatic factors showed that rice yield variability, ranging from 15.4% to 80.9%, was mainly due to precipitation and the daily temperature range during the reproductive growth and ripening stages. Climate change scenarios may result in the improvement or deterioration of rice yields across different regions. Rice yields are predicted to increase in most regions, although some southern coastal areas may experience decreased yields. This study highlights the need for strategies to address expected fluctuations in rice yield resulting from increased climate variability. These findings provide valuable insights for developing climate change adaptation measures for rice agriculture in South Korea.