Abstract: Based on the observation data from national basic meteorological station in Tianjin from 1980 to 2022,this study analyzed the temporal and spatial distribution characteristics of effective temperature (ET) in Tianjin,and discussed the differences of comfort between urban-rural areas and sea-land under the background of climate change.The results indicate that the overall climate in Tianjin showed a warming and drying trend from 1980 to 2022.The annual mean ET increased obviously,with a rate of 0.45 ℃·(10 a)^-1.The increasing trend in winter 0.9 ℃·(10 a)^-1 was higher than that in summer 0.4 ℃·(10 a)^-1.Significant spatial differences in ET were observed across Tianjin,where ET of eastern Tianjin was smaller than that of western region.There was an increasing trend of ET on inter-decadal scale in each season,the magnitude of increase became larger toward the eastern part of Tianjin.Due to the urbanization and heat island effects,the urban-rural and sea-land difference of ET in Tianjin showed a fluctuating but increasing trend year by year,with an increase of 0.5 ℃·(10 a)^-1.Due to the changes in sea-land difference of meteorological elements,the absolute value of sea-land difference of ET tended to decrease,decreasing by 0.4 ℃·(10 a)^-1(P<0.001).The difference of ET between coastal and inland areas decreased year by year.