In this paper, a cobalt-doped carbon-based compound was prepared from anhydrous glucose and cobalt nitrate hexahydrate by a combination of hydrothermal method and in situ loading, and applied as an activator of potassium monopersulfate (PMS) for catalytic degradation of tetracycline in water. The prepared cobalt-doped carbon-based compounds were characterized by XRD, SEM, TEM, XPS, etc. The reason why the degradation effect of tetracycline by this catalyst was significantly higher than that of a single hydrothermal carbon was analyzed from the aspects of crystal structure, microstructure, and surface chemical elements. In addition, the effects of catalyst dosage, PMS dosage, and solution pH on the catalytic degradation of tetracycline were investigated. The experimental results show that, under the optimal reaction conditions, the cobalt-doped carbon-based compounds catalyze the degradation of tetracycline for 60 min, the degradation rate of tetracycline reaches 95.84% (k=0.051 36 min-1). The degradation mechanism was also investigated, and the analysis results show that Co0 and Co2+ in the cobalt-doped carbon-based material are involved in the activation of potassium monopersulfate to produce ·O-2, SO·-4, 1O2,·OH, and thus the materials have the ability to catalyze the degradation of tetracycline with high efficiency, which is promising for the treatment of antibiotic wastewater.