To characterize gastrointestinal cancer survivors' ability to psychologically adjust, we examined the relationship between psychological characteristics (quality of life (QOL), anxiety, depression, and post-traumatic stress symptoms) and self-efficacy (perceived ability to initiate coping strategies). Forty-seven subjects (32 males and 15 females) were recruited from outpatient clinics or general surgical wards after readmission for therapy unrelated to cancer. All had undergone treatment for gastrointestinal cancer. Japanese version of the Functional Assessment of Cancer Therapy--General (FACT-G), Japanese version of Hospital Anxiety and Depression Scale (HADS), Japanese version of Impact of Event Scale--Revised (IES-R), and The Self-Efficacy Scale for Advanced Cancer (SEAC) were administered. Correlation analyses revealed a statistically significant positive correlation between three subscales of SEAC and QOL (total of FACT-G value) and a significant negative correlation between anxiety, depression (the total of HADS value), post-traumatic stress symptoms (the total of IES-R value), and SEAC. In multiple regression analysis, the influence from Affect Regulation Efficacy (subscale of SEAC) was the largest in anxiety and post-traumatic stress symptoms while the influence from Activities of Daily Living Efficacy (subscale of SEAC) was the largest in QOL and depression. Our findings revealed that a strong relationship between self-efficacy and psychological adjustment, and that there should be several psychological intervention forms performed at various treatment stages to enhance self-efficacy in this population of gastrointestinal cancer survivors. These results also imply the effectiveness of interventions on self-efficacy for gastrointestinal cancer survivors and the influence of psychological factors such as QOL, anxiety, depression, and post-traumatic stress symptoms.