Neck mass is a common manifestation from head and neck malignancy, most of which come from mucosal squamous cell carcinomas in the upper aero-digestive tract. However, once aspiration cytology suggests atypical malignant cells in the neck mass rather than metastatic squamous cell carcinomas, it is confusing to decide the adequate diagnostic work-ups and treatment planning. Here, we report a 29-year-old woman presenting with a growing neck mass mimicking malignancy of unknown origin, which was finally diagnosed as primary lymphoepithelial carcinoma in the parotid gland with multiple metastases to the lymph nodes. The patient underwent comprehensive neck dissection and total parotidectomy and the adjuvant radiation treatment was given. Our report highlight that the primary salivary gland cancer should be considered as the potential tumor origin in case of malignancy of unknown origin in the head and neck region and neck mass suggestive of atypical carcinomas.