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Wheat harvest (WH) largely alters the PM2.5 characteristics for rural and adjacent urban areas.A systematic PM2.5 sampling campaign was conducted in an urban area (UA) and a rural site (ARS) in the center of Beijing-Tianjin-Hebei during and after WH (DWH and AWH). PM2.5 levels (in µg m -3 ) in both ARS and UA increased from 75.5 to 156, and from 53.1 to 137 along with the transition from AWH to DWH. Hysteresis of PM2.5 peaks in UA further proved the migration effect of "Rural to Urban". High Igeo values were found for crustal elements in two sites evidencing the WH derived dust emissions. Soil dust shares in PM2.5 decreased from 9.40% to 6.75% and 21.3% to 7.98% for UA and ARS from DWH to AWH, while biomass-burning markers Cland K + increased from 3360 to 6650 and 3630 to 7500 µg g -1 for UA, and from 5050 to 9370 and 5480 to 8090 µg g -1 for ARS. Six sources were identified by PMF including coal combustion (CC), vehicle exhaust (VE), industrial source (IS), biomass burning (BB), secondary inorganic aerosol (SIA), and fugitive dust (FD). FD dominated in ARS during DWH, and higher shares occurred in AWH for UA. BB shares in two sites increased from DWH to AWH attributing to the biomass burning for maize planting. It was surprising to point out higher VE shares appeared in ARS instead of UA due to the operation of harvesters and cultivators. Much higher IS shares in UA indicated that local industrial emission control should be enhanced.Certain CC shares in both UA and ARS implied that coal was still an important fuel regardless of the government decree of "Coal Limitation".