Lignin is an important substance in defense attacks of herbirore in plants. After Pinus massioniana trees were damaged by Dendrolimus punctatus Walker，lignin contents, peroxidase activity and its isoenzyme were analyzed respectively at different times. Results indicated that lignin contents compared with the control，increased slightly at 1h from insect-damaged leaves (IDL). Instead of systemic leaves (SL) enhanced after 10 hrs. Lignin contents and peroxidase activities reached their maximum after 24hrs. Furthermore, their differences gradually enhanced with times, which were reflected in expression quantities. F test showed that lignin content corresponded with peroxidase activity and peroxidase isoenzyme changes in damaged P. massoniana needles and displayed difference significantly in 24h（P﹤0.05）.