Using a DMT(Droplet Measurement Technologies) continuous flow streamwise thermal gradient cloud condensation nuclei (CCN) counter,the aircraft and ground measurements of CCN over some regions of North China are conducted.The field observations show that,due to the severe air pollution,CCN number concentration in Taiyuan city is higher than that in Shijiazhuang city.Daily mean and maximum CCN number concentrations increase with the supersaturation.With the influence of meteorological factors and human activities,the variations of CCN number concentration display a distinctive diurnal cycle including two apparent peaks.Precipitation has an obvious scavenging effect on the ground CCN.The ground CCN spectra can be derived from the expression N=CS^k.The fitting spectra parameters C(more than 2 200 cm^-3) and k(less than 1) represent the continental characteristic of CCN in Taiyuan city.The CCN is mainly transported from surface and CCN number concentration decreases with the height.Long-distance transportation of particles provides secondary source for CCN when the upper wind direction changes.The cloud has a definite depletion effect on CCN particles so that CCN decreases obviously in clouds.