Abstract: Objective To observe the effect of Yiqi Yangyin recipe(YQYY, supplementing qi, nourishing yin) combined with postoperative adjuvant chemotherapy FOLFOX4 on immune function in patients with colorectal cancer. Methods Selected 60 patients with colorectal cancer from Department of General Surgery in Longhua Hospital received operation and were hospitalized to complete the full cycle of chemotherapy from January 2009 to June 2012. These 60 patients were equally randomized into two groups, treatment group, treated with YQYY combined with chemotherapy, and control group, treated with chemotherapy alone(n=30). Both groups received FOLFOX4 chemotherapy; moreover, treatment group took YQYY during chemotherapy, twice a day. The immune indicators were observed before and after operation, and before various cycles of chemotherapy. The changes of immune indicators and side effects of chemotherapy were analyzed. Results Index change in treatment group was not statistically significant before and after all cycles of chemotherapy. CD4, CD4/CD8 were increased after operation in treatment group and control group, but CD8 was significantly decreased (P>0.05).After 3 cycles of chemotherapy, CD8 was decreased, while CD4/CD8 was increased in both groups (P<0.05). CD3,CD4,CD4/CD8 were significantly increased while CD8 was significantly decreased after 6 cycles of chemotherapy in treatment group compared with control group（P<0.01）. The side effects of chemotherapy in treatment group were significantly lighter than those in control group. Conclusion YQYY could improve the immune function and reduce the side effects in colorectal cancer patients during postoperative adjuvant chemotherapy.