The periods of climate comfort have certainly changed over the last 50 years because of climate change. Based on daily climatic data from 170 observatories from 1966 to 2015, variations in the period of climate comfort in the Beijing-Tianjin-Hebei region over the last 50 years were examined in detail in terms of the temperature-humidity index (THI), wind-effect index (WEI), index of cloth loading (ICL), as well as the comprehensive comfort index (CCI). The start date, end date, and duration of comfortable days with annual variation characteristics were recorded so that analysis of spatial and temporal changes could be done. Evaluation of climate comfort is an important indicator of spatial distribution of the population, and assessment of climatic resources. This study on climate comfort period used daily climate data to precisely chart the intra- or inter- regional differences, especially under global climate change. Our study found:(1) In the past 50 years, the trend of change of the various comfort indices were the same for Beijing, Tianjin, and Hebei. The average annual CCI in the Beijing-Tianjin-Hebei region showed an obvious upward trend, while the various individual comfort indices showed variations among Beijing, Tianjin, and Hebei. The range of change was greatest in Tianjin, while the least change occurred in Beijing. (2) Analysis of time data showed the annual distribution of climate comfort appeared to be of the "M" type in the Beijing-Tianjin-Hebei region. By building the CCI, the comfortable period in the Beijing-Tianjin-Hebei region was concentrated mainly in the periods of April to May, and September to October, where there were more than 28 days a month graded as comfortable or less comfortable. Annually, the most comfortable period was in May, with 24-26 days graded as comfortable. Among Beijing, Tianjin and Hebei, the longest comfortable period per year occurred in Beijing, with an average of 100 days, followed by Hebei, with an average of 95 days, and the shortest comfortable period occurred in Tianjin, with an average of 91 days. (3) At the start date, as calculated by assessment of THI, WEI, and ICL, there was a significantly advanced tendency for comfortable and less comfortable grade days, whereas at the end date there was a slightly increased tendency for comfortable days, but this was not statistically significant. CCI showed that the start date of the less comfortable grade days varied greatly, advancing by 3-4 days per 10 years. The end date in Tianjin and Hebei increased at a rate of 1-2 days per 10 years, while this tendency in Beijing was not statistically significant during the 1966-2015 period of study. (4) Spatial distribution analysis showed the duration of comfortable days in the Beijing-Tianjin-Hebei region decreased from northwest to southeast. The longest duration of comfortable days was in northern Hebei, of which there was an average of 115-120 days per year, while the shortest duration was in southeast Hebei, where there was an average of less than 90 days.