Background: Cancer is a major public health problem in many parts of the world. Gastrointestinal (GI) cancers are responsible for 20% of all cancer-related deaths. In Turkey, stomach cancers account for 8.9%, colon cancer for 6.9%, and pancreatic cancer for 5.9%. This study examined the anxiety-depression levels and the quality of life of patients with GI cancer. Materials and Methods: This descriptive study was carried out on 335 adult patients who had gastrointestinal cancer and who were hospitalized in medical oncology clinics. Data were collected by using hospital anxiety and depression scale, EORTC QLQ C-30 and a patient information form. Results: Patients who were male and secondary school graduates/graduates/postgraduates experienced more functional difficulties. Patients with poor economic status experienced more symptoms. Patient general wellbeing decreased with increase disease duration. The level of functional difficulties decreased with an increasing number of hospital stays. Anxiety scores increased with decreasing age. Both anxiety and depression scores increased with increasing disease duration. Patients who were female, single/widowed/divorced, and literate/ elementary school graduates had higher anxiety and depression scores. Life quality decreased with increasing anxiety and depression. Conclusions: Patients should be supported to prevent anxiety and depression, and should be followed up with this in mind.