The convective weather and lightning disasters occurred frequently in the northeastern verge of Tibetan Plateau. In order to analyze the characteristics of cloud-to-ground (CG) lightning flashes, the CG location data and daily precipitation collected by the advanced toa and direction （ADTD） system of Gansu Provincial Meteorological Administration and CIMISS during 2017-2020 are used to investigate the spatial and temporal characteristics of the CG lightning frequency, current intensity and the CG flashes density in the northeastern verge of Tibetan Plateau, and the relationship between the CG flashes density and precipitation. The results show that the annual average number of the CG lightning in this region in recent four years was about 2.71×10⁴ times. The annual average negative CG and positive CG lightning accounted for 84.27% and 15.73% of the total CG lightning flashes, respectively. The monthly distribution of the CG lightning flashes presented a single-peak pattern. Specifically, the CG lighting flashes mainly occurred in summer, which accounted for 70.11% of the CG lightning in the whole year. In spring and autumn, the percentage of the CG lightning was less than that in summer, and in winter the number was least. The diurnal distribution of the CG lightning frequency also showed a single peak. The peak value of the total CG and negative CG lightning occurred mainly from 10:00 BST to 12:00 BST in a day. The occurring time of peak value for positive CG lightning lagged one hour than the negative CG lightning. Although the number of monthly-averaged positive CG lightning was much less than that of negative CG lightning from April to October, the ratio of average current intensity of positive CG lightning flashes to that of negative CG flash was 1.56. The CG lightning flashes density greater than 0.24 fl·km^-2·a^-1 concentrated in Yongdeng County of Lanzhou, Luqu County, Maqu County and Hezuo City in Gannan Tibetan Autonomous Prefecture, Zhangjiachuan County in Tianshui City, Huachi County, Huan County, Zhenyuan County and Qingcheng County in Qingyang City, Wen County and the south of Longnan City. And the high incidence areas of positive CG lightning mainly occurred in Maqu County, Luqu County, the junction of Dingxi City and Gannan Tibetan Autonomous, and the central and southern part of Qingyang City. Lighting protection measures should be strengthened in the above areas. By comparing the density of the CG lightning and precipitation, it is found that the spatial and temporal distributions of lightning activity was consistent with precipitation in the northeastern verge of Tibetan Plateau.