Climatic suitability can dynamically characterize the influence of climatic conditions on crops growth and development. Using the meteorological data and agrometeorological data in Chifeng district in the last 30 years,based on the fuzzy mathematics theory, the climatic suitability evaluation model in Chifeng district was established according to the demand of temperature and precipitation in each millet development period. The results showed that the climatic suitability of millet in the vegetative growth stage was generally higher in Chifeng district and the climatic suitability in the reproductive growth stage was reduced due to the higher demand of climatic conditions.The temperature demand was relatively strict in the flowering and pollination stage of millet, so the climatic suitability of this stage was slightly lower. In the last 30 years, the climatic suitability of millet in Chifeng district was above 0.5 and above 0.6 in 70% of the years, the result indicating that the climatic conditions were very suitable for the growth of millet. The results of model checking showed that the climatic suitability of millet in Chifeng district was positively correlated with the meteorological yield at 0.01 significant level, the assessment ability of the model reached a high level. The climatic suitability model of 10 days scale which was built in this study can objectively reflect the climate suitable level and dynamic change of millet in Chifeng district.