We conducted a retrospective analysis of 221 subjects with 256 suspected gastrointestinal lesions from2007 to 2015 to explore the detecting efficiency of dualtime-point fluorine-18 fludeoxyglucose(~(18)F-FDG) positron emission tomography/computed tomography(PET/CT)and pathology examination. The abdominal delayed PET/CT was performed within 45 min of the conventional scan.The change in maximum standardized uptake value(ASUV_(max)) and morphological features of the suspected lesions between the conventional and dual-time-point PET/CT were compared. The sensitivity, specificity, positive predictive value, and negative predictive value(NPV) of conventional PET/CT were 81.6%(84/103), 56.2%(86/153), 55.6%(84/151), and 81.9%(86/105), respectively.Those of dual-time-point PET/CT were 94.1%(97/103),78.4%(120/153), 74.6%(97/130), and 95.2%(120/126),respectively. There was a significant difference between the conventional and dual-time-point PET/CT(P < 0.005).The SUV_(early) and the %△SUV_(max) could not present more information in differential diagnoses, but the rate of tumors with increased SUVdelay accounted for 79.6%(82/103) and more than that of nonneoplastic lesions(15.5%, 29/187)(x~2= 115.5, P < 0.01). Therefore, the dual-time-point~(18)F-FDG PET/CT had a higher sensitivity and NPV than the conventional PET/CT to detect gastrointestinal tumors.The constant morphology and increased SUV_(delay) help to detect the tumors and adding delayed imaging on the locality will be an effective method when we accidentally find a suspected gastrointestinal tumor on the conventional PET/CT images. We conducted a retrospective analysis of 221 subjects with 256 worse gastrointestinal lesions from 2007 to 2015 to explore the detection efficiency of dualtime-point fluorine-18 fludeoxyglucose (~ (18) F-FDG) positron emission tomography / computed tomography pathology examination. The abdominal delayed PET / CT was performed within 45 min of the conventional scan. change in maximum standardized uptake value (ASUV_ (max)) and morphological features of the definitive lesions between the conventional and dual-time- point PET / The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of the conventional PET / CT were 81.6% (84/103), 56.2% (86/153), 55.6% and 81.9% (86/105) respectively. Both of the dual-time-point PET / CT were 94.1% (97/103), 78.4% (120/153), 74.6% (97/130), and 95.2% There was a significant difference between the conventional and dual-time-point PET / CT (P <0.005). The SUV_ (early) and the% ΔSUV_ (max) could not present more information in differential diagnoses, but the rate of tumors with increased SUV exposure account for 79.6% (82/103) and more than that of nonneoplastic lesions (15.5%, 29/187) (x ~ 2 = 115.5, P < 0.01). The dual-time-point ~ (18) F-FDG PET / CT had a higher sensitivity and NPV than the conventional PET / CT to detect gastrointestinal tumors. The constant morphology and increased SUV_ (delay) help to detect the tumors and adding delayed imaging on the locality will be an effective method when we accidentally find a suspected gastrointestinal tumor on the conventional PET / CT images.