Abstract: Using multi-source data, Kunming quasi-stationary front low cloud weather occurring in Guiyang Airport in February 2019 is diagnosed and analyzed. It shows that when the low cloud weather occurs in Guiyang Airport, the Kunming quasi-stationary front is located at 24°N~27.5°N and 104.5°E~109°E, the southerly airflow at 850 hPa and below provides the main source of water vapor for the occurrence of low cloud weather in Guiyang Airport under the background of quasi-stationary front. The closer to the ground, the more the water vapor source is coming from the western Pacific. The quasi-stationary front has the characteristics of shallow cold air layer when the low cloud weather occurs in Guiyang Airport. The average thickness of the cold air layer is 390 meters, the maximum thickness is 780 meters, the shallowest was only 120 meters. Ground convergence line appears more often in central Guizhou when the quasi-staionary front low cloud weather occurs in Guiyang Airport, it can be divided into three types: When the quasi-stationary front is located in western Guizhou or eastern Yunnan, the convergence line between northerly winds and southeast winds should be pay more attention; When the quasi-stationary front retreats eastward, the southward airflow near ground moves into the central and southern regions of Guizhou, and form a convergence line with the northerly airflow; When the quasi-stationary front is at the frontogenesis step, a strong cold air encounters southerly airflow in the front of Kunming thermal low pressure in central Guizhou, which generates a convergence line.