Background: accurate preoperative staging of colorectal cancer (CRC) is crucial for providing the optimal therapeutic strategy and evaluating the prognosis. The PET-CT using most frequently the radio-labeled glucose analog 18F-fluorodeoxyglucose (18F-FDG), is an imaging examination used in the staging, evaluation of treatment and therapeutic response or recurrence in many cancers including CRC. We evaluate the diagnostic performance of 18F-FDG PET-CT in the detection of CRC. Methods: a meta-analysis was conducted based on a search of PubMed, Embase and Cochrane, studies reporting the sensitivity and specificity of PET-CT, from true-positive (TP), falsepositive (FP), true negative (TN) and false-negative (FN) and in reference of histological evidence. The QUADAS criteria were used in the qualitative evaluation of the studies. Results: 29 studies were included in this meta-analysis, with a total of 16. 824 patients. The PET-CT had a sensitivity of 0.51 (95% CI: 0.35-0.66) and a specificity of 0.95 (95% CI: 0.90-0.99). The PET-CT had a positive likelihood ratio of 7.2 (95% CI 5,2-10) and a negative likelihood ratio of 0.55 (95% CI 0,36-0,84). The sensitivity analysis revealed a sensitivity of 0.49 (95% CI 0.27-0.71) and a specificity of 0.93 (95% CI 0.89-0.96) respectively, which the AUC was 0.9 (95% CI 0.87-0.92). Conclusion: our meta-analysis suggested the PET-CT could be a promising complementary examination for the detection of preoperative CRC lesions with a good performance and probably more specific way for advanced or preocclusive lesions, beyond its routine use for extension staging.