The incidence of cardiac metastasis of hepatocellular carcinoma (HCC) is about 1-4% and especially metastasis to right atrium (RA) is very rare, with an incidence of only 0.7-3% in a postmortem series. But, most RA tumors associated with HCC are intracardiac metastasis and the occurrence of synchronous primary RA myxoma and HCC is extremely rare. We report one case that a cardiac mass was primary RA myxoma initially misdiagnosed as occult HCC with intracardiac metastasis.