To explore the synergistic effects of different catechins on antioxidant and bacteriostasis compared with single catechins, in order to achieve the application of reducing dose and increasing efficiency. The scavenging ability of four single catechins (EGCG, ECG, EGC, EC) on DPPH free radicals was compared under the concentration gradient of 0.025~0.2 mg/mL. The optimal combination of different catechins was investigated based on orthogonal design with antioxidant properties (DPPH free radical scavenging ability) as the index. In the experimental concentration gradient, the best combination was set as three different concentrations of high, middle and low groups, and the inhibitory effects of different complex catechins on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were compared. The antioxidant and antibacterial effects of complex catechins were better than those of single catechins. The best antioxidant effects of catechins were 0.1 mg/mL EGCG, 0.025 mg/mL EC, 0.1 mg/mL ECG, 0.05 mg/mL EGC (volume ratio 1:1:1:1). The scavenging rate of DPPH free radical reached 95.03%, which was significantly better than that of EGCG at 0.1 mg/mL concentration (p <0.05), and the antibacterial effect of high, medium and low concentrations of complex catechins on S. aureus and E. coli was better than that of the four single catechins. Compared with single catechin, the optimized complex catechins showed better DPPH free radical scavenging ability and inhibition of S. aureus and E. coli, it shows that they have synergistic effect.