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Objective: The aim of the study was to evaluate the usefulness of (99m)Tc-pertechnetate whole body scan (WBS) with neck and chest SPECT/CT for detection of post-surgical thyroid remnant and metastasis in differentiated thyroid cancer (DTC) patients., Methods: Fifty-six post total thyroidectomy patients were included. All patients were prospectively imaged with (99m)Tc-pertechnetate WBS with neck and chest SPECT/CT before (131)I ablation. The post-ablative (131)I WBS with SPECT/CT was performed at 5-7 days after receiving (131)I. Both scans were directly compared to determine the concordance of sites and number of remnant and metastasis., Results: Overall per-patient analysis, the percentage of concordance between two scans was 96.4%. In thyroid bed, lymph node, lung and bone subgroups, the percentage of concordance between two scans was 96.4, 92.9, 98.2 and 100%, respectively. All of them show good correlation with unweighted kappa between 0.7 and 1. Overall per-lesion analysis, the percentage of concordance between two scans was 84%. In thyroid bed, lymph node, lung and bone subgroups, the percentage of concordance between two scans was 89.5, 55, 82.6 and 50%, respectively., Conclusions: Pre-ablative pertechnetate WBS with neck and chest SPECT/CT has good correlation for the detection of post-surgical thyroid remnant, cervical node and discrete lung nodule metastasis as compared to (131)I WBS with SPECT/CT per-patient basis. Because (131)I therapeutic activity is desired base on metastatic site and less concerning about the number of lesions, pre-ablative (99m)Tc-pertechnetate WBS with SPECT/CT was a good alternative tool to avoid radioiodine stunning in post-surgical DTC patients.