Abstract: Based on the method of statistical analysis, the author established the correlation of growth period length, meteorological factors and maize yield by using the observation data of daily mean temperature, maximum temperature, minimum temperature, sunshine duration and maize yield in the growth and development stages from 1984 to 2011 of 4 observation stations, including Linhe in Hetao irrigated area, Urad Front Banner, Jungar Banner and Tumed Left Banner. The results showed that there was a strong relationship between maize high yield and the local appropriate weather conditions. Moreover, comprehensive assessment of agricultural climate adaptability of maize growth in Hetao irrigated area was conducted by the method of multiple integral regression, the effects of temperature and sunshine duration on yield were confirmed. The results showed that late April to early May and middle of July to early September were 2 key stages of heat demand. The light condition could satisfy the needs of growth, while temperature was slightly high and played a dominant role. Sunshine condition had a positive effect on maize yield from middle of May to late June and in whole September. When the amount of sunshine duration increased 1 hour, the yield of maize increased 2.6 kg/(hm²·h) and 4.1 kg/(hm²·h).