Introduction: Chest pain is a very frequent reason for seeking medical care. When there is no obvious cause, patients are sometimes subjected to tests and treatments that may be unnecessary and potentially harmful. Mondor's disease is a rare but usually benign and self-limited entity characterized by thrombophlebitis in a specific region. Case report: We report the clinical case of a 51-year-old man admitted to the emergency department with a 24-hour history of left chest pain with no other symptoms. Physical examination revealed a palpable subcutaneous cord-like structure that ultrasound confirmed to be thrombophlebitis of a superficial vein in the mammary region. Secondary causes were ruled out, and the condition resolved with ibuprofen and the application of local ice. Discussion: Mondor’s disease can be associated with neoplasms, trauma or hyperviscosity states, but it is mostly idiopathic. Usually, it resolves completely in 4–8 weeks without specific treatment. Because this infrequent diagnosis mainly relies on clinical findings, it is important that clinicians can recognize the syndrome.