The aim of the study is to highlight the role of PET-CT in assessment of post-operative colorectal cancer to allow detection of local recurrence or distant metastasis so the clinician makes the best management plan. Twenty-five post-operative patients with colorectal carcinoma underwent FDG PET-CT. The final histopathological and/or at least 6 months of clinical and radiological follow-up were used as reference standard to make sure of the final diagnosis of recurrence or metastasis and decide the specificity and sensitivity of FDG PET-CT and enhanced CT of the same periods. Out of the 25 patients were included in the study, PET-CT was positive for recurrent colorectal cancer either local recurrence or distant metastasis in 16 patients (64 %) and negative in 9 patients (36 %). PET- CT show high accuracy, specificity, and sensitivity in detection of local recurrence 96%, 94.1%, and 100% respectively, and 100% sensitivity, accuracy and specificity in detecting hepatic and extra hepatic metastasis. PET/CT showed superior diagnostic performance in detecting recurrence either local or distant metastasis in post-operative colorectal cancer with high sensitivity, accuracy and specificity and it is advisable to be used in surveillance of postoperative colorectal patients.