Abstract: Based on the daily meteorological data in the Hohhot-Baotou-Ordos region from 1970 to 2019, the daily temperature-humidity index (THI), wind-efficiency index (WEI), index of clothing (ICL), and comprehensive comfort index (CCI) were used as the evaluation index for climate comfort.The characteristics of the climate comfort index, the key meteorological factors affecting the index, and the spatial distribution characteristics of comfortable days in this region were analyzed using trend analysis, Mann-Kendall test and path analysis.The results show that WHI, WEI and CCI show a significant upward trend, while ICL shows a significant downward trend.The comfort period is from April to October.The number of comfortable days reaches 68%-93% from May to September.The whole period from June to August is comfortable or relatively comfortable.Under the background of climate change in central Inner Mongolia in the 1990s, the comfort of the temperature, humidity and wind efficiency changed towards warm.The comprehensive comfort of the human body is getting better and better, which is suitable to live, travel and take summer vacation.Temperature and wind speed are the key meteorological factors to affect the climate comfort in the region, followed by sunshine.The number of comfortable and relatively comfortable days is less in the north and than in the south.As a whole, the number of comfortable days shows a fluctuating change.Compared with comfortable days, the number of relatively comfortable days continuously increases.Industrial production, human activities and the ecological environment affect the number of comfortable or relatively comfortable days.This study provides a scientific basis for the evaluation of the human settlement environment and summer tourism conditions, rational development of tourism resources, optimal development of future urban agglomerations, and the industrial expansion of urban construction and human activities.It provides theoretical support for the analysis of climate comfort change characteristics and key meteorological factors in a specific region.