Abstract： Objective： To observe the clinical effect of modified Banxia Xiexin Decoction for gastrointestinal dysfunction of disharmony between liver and spleen type after colorectal cancer surgery and its effect on serum tumor markers. Methods： A total of 105 cases of patients with gastrointestinal dysfunction of disharmony between liver and spleen type after radical resection of colorectal cancer were enrolled and divided into the study group and the control group according to the random number table method，with 53 and 52 cases in each group respectively. After surgery，both groups were given routine treatment such as enteral nutrition support and water electrolyte balance； the control group was additionally given Loperamide Hydrochloride Capsules and Metoclopramide Injection for symptomatic treatment； the study group was additionally treated with modified Banxia Xiexin Decoction. After treatment， the clinical effects， the traditional Chinese medicine (TCM) syndrome scores， the recovery time of gastrointestinal function， and the levels of serum tumor markers including carbohydrate antigen 199 (CA199)，carbohydrate antigen 724 (CA724)，and carcinoembryonic antigen (CEA) in the two groups were observed. Results： The total effective rate was 98.11% in the study group， higher than that of 86.54% in the control group， the difference being significant (P＜0.05). Before treatment， there was no significant difference being found in the comparison of TCM syndrome scores between the two groups (P＞ 0.05)； after treatment， TCM syndrome scores in the two groups were decreased when compared with those before treatment (P＜0.05)，and TCM syndrome scores in the study group were lower than those in the control group (P＜0.05). The first exhaust time， the first defecation time， and the recovery time of bowel sound in the study group were significantly earlier than those in the control group，differences being significant (P＜0.05). Before treatment，there was no significant difference being found in the comparison of levels of CA199，CA724，and CEA in serum between the two groups (P＞0.05)；after treatment，the above indexes in the two groups were decreased when compared with those before treatment (P＜0.05)， and the indexes in the study group were lower than those in the control group (P＜0.05). Conclusion： Modified Banxia Xiexin Decoction has a significant curative effect in the treatment of gastrointestinal dysfunction of disharmony between liver and spleen type after colorectal cancer surgery，which can downregulate the levels of serum tumor markers， help relieve clinical symptoms of patients and promote the recovery of gastrointestinal function.