Abstract: ［Abstract］Objective　To investigate the value of multi-layer spiral CT enhancement scanning combined with 3 d imaging in diagnosis of common thyroid diseases．Method　We retrospectively analysed the spiral CT imaging characteristics of 72 cases of thyroid lesions confirmed by surgery and pathology．Results　In 36 cases of nodular goiter，31 cases showed circular uniform or non-uniform slightly low density，3 cases showed equal density，2 cases showed mixed high and low density. 16 cases showed mild circle enhancement and 20 cases showed non-enhancement after enhancement scan lesions. 8 cases of thyroid adenoma showed circular uniform or non-uniform slightly low density after CT plain scan，and showed middle enforcement or uneven enforcement in solid after enforcement scan，among them， 2 cases showed enforced wall nodules，and 2 cases showed obviously enforced envelope，2 cases of cystic degeneration of adenoma and bleeding showed equal density without enforcement．In 14 cases of thyroid carcinoma，7 cases showed circular uneven slightly lower hybrid density，3 cases showed round like or irregular solid mass，and showed obviously uneven enforcement，no no envelope reinforcement or non-complete enforcement ring，2 cases showed neck lymph node metastasis．12 cases of nodular goiter with follicular adenoma or local adenomatoid hyperplasia and 4 cases of nodular goiter with tiny papillary carcinoma had similar performance，CT plain scan showed multi center circular uneven low，slightly lower hybrid density and showed local uneven light - moderate enforced nodules in the lesion area after enforcement scan． Conclusion　Multi-slice spiral CT scanning combined with 3 d imaging can reflect the form，size，density，number of thyroid lesions，their relationship with the surrounding tissue structure，and lymph nodes in the neck，so has diagnostic value in identification of benign and malignant thyroid lesions.