Based on the hourly observation data of black carbon (BC) and ozone (O₃) at Nanjing ground station from 2016 to 2017, the relationship between BC and near surface O₃ in different seasons was analyzed.Results shows that the O₃ value under the influence of high BC (higher than average) is significantly lower than that under the influence of low BC (lower than average).The inhibition effect is obviously stronger in autumn and winter than in spring and summer, and the negative correlation between BC and O₃ is significantly higher in autumn and winter than in spring and summer, while the negative correlation between PM_2.5 and O₃ is not significant.Based on the WRF-Chem model, the numerical simulations of BC feedback effect on O₃ are carried out for the cases in December 2017, and the results confirm that BC has negative feedback effect on O₃.The influencing mechanisms are as follows:BC can reduce the photochemical production of ozone (VOCs control area) by inhibiting the development of boundary layer and accumulating NO_x near the ground;BC can reduce the downward turbulent transport of high O₃ in the upper part of the boundary layer by suppressing the vertical turbulent exchange in the boundary layer, so as to reduce O₃ near the ground;BC can reduce the advection input of O₃ from upwind region by reducing the near ground wind speed, so as to reduce the ground O₃.The main control factors of the cases are different and should be analyzed in detail.