The clinical data of a case of anaplastic large cell lymphoma (ALCL) misdiagnosed as inflammation was reviewed and analyzed. This patient had cellulitis incision and drainage in left parotid gland to remove the mass and the mass was considered as (left parotid gland) inflammatory granulation tissue. Thus, the patient received anti-inflammatory therapy in other hospital for more than 10 days. One month later after discharge, the patient was sent to our hospital because of the pain in left humerus. Pathological examination of left humeral puncture biopsy suggested ALCL. Left parotid gland surgery specimen section and immunohistochemical inspection result revealed ALCL. When patient’s mass had no obvious inducement, microscopic appearance initially showed inflammation yet clinical anti-inflammatory treatment was ineffective. Thus, the patient was suspected to suffer from lymphoma. It needs to be rational and comprehensive to choose immunohistochemical indicators and improve the awareness of lymphoma of this kind and elevate the pathological diagnostic level.