No further details were given in the health ministry statement carried by the official ONA news agency. It is the third MERS fatality in the Gulf sultanate.
Oman borders Saudi Arabia, the country hardest hit by MERS.
MERS is considered a deadlier but less transmissible cousin of the SARS virus that appeared in Asia in 2003 and infected more than 8,000 people, nine percent of whom died.
Like SARS, it appears to cause a lung infection, with patients suffering coughing, breathing difficulties and a temperature. But MERS differs in that it can cause rapid kidney failure.