Objective To explore the clinical manifestations of ultrasonography（US）, 99mTc-methoxyisobutylisonitrile (99mTc-MIBI), and 131I whole body scan (131I-WBS) of patients with differentiated thyroid carcinoma（DTC）and cervical lymph node metastasis. Methods A total of 117 cases received examinations of US and 99mTc-MIBI before uses of 131I and received 131I-WBS after 6 d of 131I treatment. Combined with serum thyroglobulin（Tg）, 131I-SPECT/CT, lymph node biopsy and clinical follow-up of patients, cervical lymph node metastases were identified. Results In 117 patients, the sensitivity of US, 99mTc-MIBI and 131I-WBS were 76.5%, 67.1% and 83.5%（P<0.05）; the specificity of US, 99mTc-MIBI, and 131I-WBS were 75.0%, 78.1% and 84.4%; and the accuracy of US, 99mTc-MIBI and 131I-WBS were 76.1%, 70.1% and 83.8% (P<0.05), respectively. The total sensitivity, total specificity, and total accuracy of combination of the three examinations were 98.8%, 75.0% and 92.3%, respectively. Detection rates by US, 99mTc-MIBI, and 131I-WBS of 134 cervical lymph node metastasis were 75.4%, 66.4% and 80.6% (P<0.05). Combined US with 99mTc-MIBI, detection rate for 26 false-negative 131I-WBS imaging was 96.2%. Conclusion The combination of US, 99mTc-MIBI, and 131I-WBS could improve the sensitivity, specificity, and accuracy of post-operative cervical lymph node metastases of DTC. The combined results of US and 99mTc-MIBI could detect false-negative 131I-WBS imaging.