NCEP/NCAR reanalysis data and ozone and methane data of HALOE are used to study the lower-stratospheric(100 to 50 hPa) temperature trends and its relations to tracers likes ozone and methane and the mean zonal wind.The results indicate that the global temperature in the lower stratosphere trends to decrease since 1948,and the phenomenon is severer during recent ten or more years;the increase of the lower-stratospheric methane over tropics and lower latitudes may be a great cause for the temperature trends;besides,the difference of temperature variability between different zonal belts may modify the mean zonal wind.