We report the case of a 41-year-old man with symptoms of exertional dyspnoea and easy fatigue. Physical examination revealed a palpable mass with knocking pain over the right flank region and a cardiac murmur with jugular vein engorgement. Transoesophageal echocardiography revealed a right atrial mass that caused tricuspid inflow obstruction. Computed tomography revealed a giant mass (approximately 15 x 15 cm2) in the right kidney; this finding was consistent with renal cell carcinoma. Despite the metastatic status, right nephrectomy was performed and the intra-atrial tumour thrombus (TT) was resected under a cardiopulmonary bypass in order to relieve the tricuspid obstruction. Histological examination confirmed renal cell carcinoma with TT. The patient is healthy with satisfactory systolic function at 1-year follow-up.