In this paper, 18F-FDG PET/CT data of 19 malignant SINs (small intestinal neoplasms) were consecutively reviewed. Nnine patients accepted PET/CT scan for preoperative diagnosis and staging, while ten patients presented follow-up after treatment and restaging. The results were correlated with abdomen enhanced CT and surgical pathological findings. Abdominal pain and weight loss were the most common findings. About 16% SINs located in the duodenum, 52% in the jejunum and 32% in the ileum. Lymphoma was the most frequent neoplasms. PET/CT revealed residual or recurrent malignant SINs in 5 patients who had negative or non-definite findings by abdomen CT and demonstrated extra-abdomen metastasis in 3 patients. Clinical decisions of treatment were changed for 6 patients after PET/CT examinations. The 18F-FDG PET/CT were better than CT in accuracy, negative predictive value and positive predictive value (89.5% vs 68.4%, 100% vs 66.7%, and 81.8% vs 69.2%, respectively). Whole body 18F-FDG PET/CT may be an effective molecular imaging method for staging and restaging of malignant SINs. Nnine patients accepted PET / CT scan for preoperative diagnosis and staging, while ten patients presented follow-up after treatment and restaging. The paper, 18F-FDG PET / CT data of 19 malignant SINs (small intestinal neoplasms) Results were correlated with abdomen enhanced CT and surgical pathological findings. Abdominal pain and weight loss were the most common findings. About 16% SINs located in the duodenum, 52% in the jejunum and 32% in the ileum. Lymphoma was the most frequent neoplasms . PET / CT revealed residual or recurrent malignant SINs in 5 patients who had negative or non-definite findings by abdomen CT and demonstrated extra-abdomen metastasis in 3 patients. Clinical decisions of treatment were changed for 6 patients after PET / CT examinations. The 18F-FDG PET / CT were better than CT in accuracy, negative predictive value and positive predictive value (89.5% vs 68.4%, 100% vs 66.7%, and 81.8% vs 69.2%, respectively) C T may be an effective molecular imaging method for staging and restaging of malignant SINs.