With the development of the chemical industry, nitrogen-containing heterocyclic compounds constantly enters the environment, which increases the threat to the ecological environment. The degradation characteristics of the nitrogen-containing heterocyclic compounds 2，6-dichloropyridine（2，6-DCLPY） in chemical wastewater by UV/H2O2 were investigated, and the concentration of 2，6-DCLPY in the degradation process was determined by ultraviolet spectrophotometry. The influencing factors of 2，6-DCLPY degradation reaction including initial 2，6-DCLPY concentration，H2O2 concentration, pH and coexisting anions were studied. The results showed that the degradation of 2，6-DCLPY under UV/H2O2 system accorded with quasi-first-order reaction kinetics. Hydroxyl radical （·OH） was the main active substance for degradation of 2，6-DCLPY, while UV played a synergistic effect. The degradation efficiency of 2，6-DCLPY gradually increased with the increasing H2O2 dosage, and the highest degradation rate could reach 77.3% when the molar ratio of H2O2 and 2，6-DCLPY was 37 ∶ 1 and the pH was 7.2. The coexisting anions HCO3- and NO3- can directly react with ·OH, which leaded to significant inhibitory effect on the degradation reaction. The presence of electron-donating groups such as amino groups on the pyridine ring is conducive to the degradation of pyridine pollutants，while electron-withdrawing groups such as chlorine inhibits the degradation of pyridine pollutants.