To clarify the intraoral color Doppler sonographic features of tongue cancer in relation to cervical lymph node metastasis.Thirty-one patients (24 men and 7 women; 32-87 years old; median 60.6 years) with T1-2 N0 squamous cell carcinoma of the tongue were enrolled. Preoperative clinical information and sonographic findings were collected. Patients were followed up for 2 years or more, and the presence of delayed lymph node metastasis was investigated. Significant clinical and sonographic factors were evaluated in relation to lymph node metastasis.Significant differences in maximum and minimum tumor size, clinical type, tumor depth and thickness, shape of the invading front of the tumor, vascular index (VI) of the tumor area, and asymmetry of the VI of the deep lingual artery were observed between patients with cervical lymph node metastasis and those without. The areas under the curve (AUCs) of tumor thickness and the VI of the tumor area were 0.861 and 0.909, respectively, on receiver operating characteristic (ROC) curve analysis for predicting lymph node metastasis. The AUC for the VI showed a slightly higher value, although the difference was not significant (P = .532).Intraoral color Doppler sonography is recommended, as it may identify predictive factors of cervical lymph node metastasis.