Background: Thyroid oncocytic carcinoma (Hürthle cell carcinoma) is a distinct subtype of differentiated thyroid cancer (DTC) with controversial responses to radioiodine therapy. This study evaluates the treatment response of oncocytic carcinoma patients undergoing radioiodine therapy at a single center in India. Objectives: To assess the tumor characteristics, treatment strategies, and therapeutic outcomes of thyroid oncocytic carcinoma patients treated with radioiodine therapy. Methods: A retrospective analysis was conducted on patients diagnosed with thyroid oncocytic carcinoma who received radioiodine therapy. Data collected included TNM staging, administered radioiodine doses, follow-up duration, and treatment response at one year and final follow-up. Results: The mean age at diagnosis was 55.21 years (SD = 12.7), with a male-to-female ratio of approximately 1:1.2. Multifocality was observed in 4 patients (16%). Most patients (67.5%) received a total radioiodine dose between 0-200 mCi. At one-year follow-up, treatment responses included 27.6% excellent, 22% indeterminate, 22% biochemical incomplete response (BIR), and 34.2% structural incomplete response (SIR). Final responses showed improvement, with 45.3% achieving excellent response and a decline in BIR (12.1%) but persistence of SIR (45.3%). Conclusion: The study highlights that a significant proportion of Hürthle cell carcinoma patients exhibit incomplete responses to radioiodine therapy, particularly structural incomplete response. These findings suggest the need for tailored therapeutic strategies to improve patient outcomes.