It is important to study the climatic potential productivity of corn through the evaluation of the natural resource situation of corn production, including light, heat, and water. Based on the daily weather data from the meteorological stations during 1985-2015 of the West Liao River Basin, and applying the GAEZ 3.0 model, this paper analyzed the climatic characteristic and corn climatic potential productivity during the past 30 years, and evaluated the main climatic factors influencing corn potential yield of the West Liao River Basin. Results showed that the temperature of corn growth period was increasing but the precipitation was decreasing during 1985-2015. The light-temperature potential productivity (LTPP) was 12.52-13.40 t/hm~2 and climatic potential productivity (CPP) was 2.41-7.05 t/hm~2 during 1985-2015. LTPP varied slightly during 1985-2015 while climatic CPP was in fluctuation. The spatial difference of corn potential yield was obvious: the average annual variation of LTPP increased from south to north in the West Liao River Basin, and the high value of CPP was located in the northeast region of West Liao River Basin. Precipitation was the top contributor of corn CPP in the West Liao River Basin. In conclusion, the expansion of irrigation area was an effective way in corn production growth, while the influence of temperature to CPP was relatively weak.