Branchial cleft cyst is the most common lateral neck cyst; the vast majority are of the second branchial cleft origin. This presumably reflects the greater depth and longer persistence of the second cleft, compared with the first, third, and fourth clefts. We experienced a 49-year-old male whose chief complaint was a abnormal mass of the left parotid gland area and neck. As a result of careful analysis of clinical, radiological, and histopathological findings, we diagnosed it as a second branchial cleft cyst in the neck and obtained results as follows: 1. In clinical examination, there was a 10×15㎝ sized, fluctuant painful mass in the left neck and parotid area. 2. In radiographic examination, a low echogenic mass with internal cystic change in the inferior parotid gland area was noted sonographically. Computed tomograph showed a 3×4㎝ sized, well-defined cystic mass with heterogenous solid component in the anterior border of sternocleidomastoid muscle. MRI revealed 5×6㎝ sized, well-marginated multi separated mass in the same area. 3. In histopathological examination, lining of cyst was stratified squamous epithelium with typical lymph node pattern and inflammatory cell infiltration. branchial cleft cyst, sternocleidomastoid muscle