Single-atom catalysts with a maximum atomic utilization are promising in wastewater treatment. Herein, a single-atom dispersed Co-N-C catalyst was prepared by a calcination-acid treatment method. The obtained Co-NC was confirmed to possess excellent performances of both adsorption and catalytic ability of activating peroxymonosulfate (PMS). It was found that the adsorption performance was related to the surface area and pore volume and the removal of bisphenol A (BPA) was determined by the defect density of the catalyst. It was observed that a calcination temperature of 900 degrees C yielded the best Co-N-C catalyst named Co-N-C-900. All the added BPA (80 mg L-1) was completely degraded in 3 min by using 0.5 g L-1 Co-N-C-900 and 0.3 g L-1 PMS with a degradation rate constant (k) of as high as 2.81 min(-1). In this single-atom catalytic system, the main reactive species were confirmed to be singlet oxygen. A mechanism study suggested that the fast and efficient degradation of BPA was attributed to the synergistic effect between fast adsorption of mesoporous carbon and efficient catalysis of single-atom Co-N-x complex.