Abstract: To address PM2.5 pollution problem and develop effective mitigation strategies in plateau mountainous city,the hourly average concentration of PM2.5 and meteorological elements in Kunming from April 2014 to March 2015 have been taken to explore the temporal and spatial distribution of PM2.5 concentrations and relationships between PM2.5 concentrations and meteorological factors with the Original Kriging interpolation and nonparametric statistical analysis methods.Results show that PM2.5 highest in spring followed in winter,and lower concentration in Kunming in the autumn and summer.The diurnal variation curves of PM2.5 concentrations present bimodal and single valley with high concentration in a.m.and low in p.m.This trend varies with the morning rush hours and meteorological conditions of the same day.The Original Kriging interpolation results show that the high PM2.5 concentration distributed in northwest part to southeast part of Kunming.And the PM2.5 concentration of the Wuhua and Panlong districts is generally higher than that of the Xishan and Chenggong districts.By the Spearman rank correlation analyses,it has demonstrated that meteorological factors such as daily average temperature,atmospheric pressure and wind speed had significant influence on the concentration of PM2.5 for the seasonal distribution.