Thymomas are rare neoplasm of Anterior Mediastinum originating within the epithelial cells of the thymus and it is exceedingly uncommon in children and young adults, rises in incidence in middle age, and peaks in the seventh decade of life. One third to one half of patients present with an asymptomatic anterior mediastinal mass on chest radiograph, one third present with local symptoms (cough, chest pain, superior vena cava syndrome, and/or dysphagia), and one third of cases are detected during the evaluation of myasthenia gravis. Myasthenia gravis is a disease of the neuromuscular junction which causes progressive weakness of muscles. Indication of thymectomy for all cases of myasthenia gravis has been a topic of debate but thymectomy is indicated in all cases with thymomas no matter the stage of myasthenia gravis. We present a rare case of Thymoma as 70/Female patient presented with a painful lateral neck swelling on left side with Myasthenia Gravis and Dysphagia. We couldnt find any similar cases in literature. USG Neck was done which showed a 5.3x5.3x4.3cm multilobulated mass in left supraclavicular region inferior to left lobe of thyroid with calcification suspicious of malignancy which possible origin from Thyroid and Parathyroid Gland. On CECT scan there was 4.1x3.4x3.8 cm isodense mass which seems to be arising from lower pole of left thyroid lobe and extending in surrounding structures. FNAC was s/o Thymoma type A. Patient underwent Sternotomy- entire tumor along with thymus was dissected, however posteriorly it was densely adhered to Left Vagus Nerve Giving Suspicion of Neurofibroma. Specimen Sent for Frozen Section which confirmed it to be Type A thymoma. Histopathology Report concluded the diagnosis- Type A Thymoma. Post Operative was Uneventful. Thus, we conclude a rare case of Neck Swelling with series of event to reach to a Final Diagnosis of Thymoma.