Malignant lymphoma is the tumor of immune system which is known as the most common nonepitheloid tumor of head and neck region. It is mainly found in the cervical, axillary and inguinal lymph node, but gastrointestinal tract, palatine tonsil, nasopharynx, oropharynx, nasal cavity and salivary glands may be involved. Primary lymphoma of the thyroid gland is an uncommon condition, comprising approximately 2% of all malignant lymphoma and 5% of all thyroid malignant neoplasms. Recently, we experienced a case of malignant lymphoma of the thyroid gland, which was histopathologically proven. So we report our findings in this patient with review of literatures.