Abstract: Objective To investigate health behavior self-efficacy among gastrointestinal cancer patients after surgery and chemotherapy，and to analyze factors that influence it. Methods A total of 586 gastrointestinal cancer patients filled out a question-naire about self-efficacy，demographic characteristics and clinical disease information. Results The overall score of health behavior self-efficacy was 71.50 ± 16.08 for patients.Only 132（22%） patients scored over 80%.Patient nutritional status，education and medical care positively correlated with general self-efficacy（P<0.05），while age，clinical stage，chronic disease，stoma and metastasis negatively correlated with it（P<0.05）.Stoma，chronic disease，nutritional status and age were the main predictors of self-efficacy. Conclusions Health behavior self-efficacy is still at a low level in most gastrointestinal cancer patients，which should be taken into account when designing and implementing clinical care.Efforts are needed to help patients adopt and maintain a health-promoting lifestyle in order to improve their quality of life.

Key words: Gastrointestinal neoplasms, Self-efficacy, Nursing, Logistic regression analysis