Abdominal ultrasound is of some significance for checking malignant tumors of abdominal parenchymal organs, but it is less effective for checking gastrointestinal diseases, and it cannot identify gastric or intestinal cancers. Abdominal ultrasound is commonly used for checking abdominal diseases. It is effective in checking organs such as liver, pancreas, kidneys, gallbladder, etc. It can find occupying lesions in liver, pancreas, kidneys or elevated lesions in gallbladder, and it is mostly used for the initial screening of the above mentioned organ diseases. However, ultrasound is less effective for gas-containing or cavity organs, such as the gastrointestinal tract and lungs, which are generally not selected for ultrasound examination. Gastroenteroscopy is the best way to examine and identify gastrointestinal malignant tumors such as gastric cancer and intestinal cancer, which can not only observe the lesions under direct vision, but also take biopsies for pathology examination to further clarify the diagnosis. If there are contraindications to gastroenteroscopy, enhanced CT or barium X-ray imaging can also be performed, but the effect is not as effective as endoscopy. Patients suspected of having malignant tumors in the digestive tract are recommended to go to the hospital as soon as possible, choose the appropriate means of examination under the guidance of professional doctors, and make a clear diagnosis as soon as possible and then be treated accordingly.