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Based on the observation data of 8 meteorological stations in the southern Hebei Province from 1962 to 2018, the characteristics and trends of climate change in summer maize growing season (June to September) are analyzed by the regression analysis, wavelet analysis and MannKendall test. The frequency of drought in the seedling stage of summer maize was 31.5%. After 1966, the climate in the seedling stage showed a humidification trend. A sudden change in climate humidification occurred around 1968 and 2009. The drywet changes during the entire analysis period (1962 to 2018) contained the periodic oscillations of 13 to 18 years and 5 to 8 years. The frequency of drought at the ear stage of summer corn was 40.3%, and the climate at the ear stage after 2006 showed a continuous aridity trend. A sudden change in climate aridification occurred around 1980 and 1997. The drywet changes in the entire analysis period contained the periodic oscillations of 15 to 22 years and 6 to 10 years. The frequency of drought during the flower and grain period of summer maize was 29.8%. After 1989, the climate during the flower and grain period showed a continuous aridification trend. It is possible that a sudden change of climate aridity occurred in 1992 and 2002. The frequency of drought in the summer corn growing season is about 30%. The climate in the growing season showed a trend of aridification, especially after 1997, and there experienced abrupt climate aridification around 1996. The above results are expected to provide a theoretical basis for drought disaster monitoring, prediction, early warning and prevention.