Abstract:health risk of black carbon aerosol in the southern suburb of Shijiazhuang city,the monitoring data ofblack carbon aerosol from August 2018 to April 2021 were analyzed by using the PivotTable method andhealth risk assessment model. The results showed that the average concentration of BC in PM2.5was 3.03μg/m3. The average concentration of BC in PM2.5in spring,summer,autumn and winter was 2.12,1.76,3.24 and 4.45 μg/m3,respectively. The diurnal variation in spring,summer and autumn was bi⁃modal and single valley,while in winter it was bimodal and double valley. The cancer risks (CR) of a⁃dults and children were higher than the acceptable risk level (10-6) given by the EPA. The orders ofCRvalue and hazard quotient(HQ)value before and after the outbreak of COVID-19 were both extremelyheavy physical activity > heavy physical activity > medium physical activity > slight activity. However,theHQof extremely heavy physical activity did not reach the threshold value,indicating that the non-car⁃cinogenic effect of BC during extremely heavy physical activity was not significant. Close-