Abstract: The effect of extract of pine needle on colonic antioxidant capacity and fecal excretion of chronic constipated mice was investigated.Seventy- six mice were randomly divided into control group, constipated group, three dose groups ( 1 ∶ 1, 1 ∶ 20, 1 ∶ 40 g ∶ m L pine needle) and positive group ( 1 ∶ 20 g ∶ m L rhubarb) . The constipated group was induced by lomotil solution ( 5mg / kg BW) once a day for two weeks. Three dose groups were given intervention with relevant extract of pine needle and others were given saline. One week later, defecation function and colonic antioxidant capacity was tested. To data, MDA was remarkably increased in colon after two weeks lomotil treatment.After the intervention of pine needle, the laxative activity of the mice was enhanced ( p < 0.05) ;SOD, GSH- Px activity was improved and MDA, NO content was decreased ( p < 0.05) . The results lead to the conclusion that the pine needle extract can improve colonic antioxidant capacity of constipated mice and relieve constipation.