According to the observations of wind data analysis from Lband radar at Yangjiang radiosonde station of Guangdong, there sometimes appear some cases of inconsistence with the theoretical values if using comprehensive detection radar or no slant distance (or height replacement) wind measurement methods to calculate the results at the wind measurement levels．The results from these two methods in wind measuring are sometimes beyond the permitted error range of upperlevel meteorological observation instruments for overall measurement accuracy. Results show that when the radar elevation angle is less than 30° and the wind speed of the wind measurement level is <3 m/s, the wind speeds calculated from the two kinds of wind methods are almost the same， with the errors within the permitted range, but there are large differences sometimes in wind direction, beyond the allowed error range. When radar elevation angle is less than 15° and the wind speed in the wind measurement level is >30 m/s, the wind directions in the measure wind layer calculated by the two methods are close, but the differences in wind speed in the wind measurement levels are comparatively large, also beyond the allowed error range.