The latest victims were a man in Riyadh and a woman in the port city of Jeddah, both in their 70s, the health ministry website said.
It said the total number of infections was now 540.
Other nations including Egypt, Jordan, Lebanon, the Netherlands, the United Arab Emirates and the United States have also recorded cases, mostly in people who had been in Saudi Arabia.
Middle East Respiratory Syndrome is considered a deadlier but less transmissible cousin of the SARS virus that appeared in Asia in 2003 and infected 8,273 people, nine percent of whom died.
Like SARS, MERS appears to cause a lung infection, with patients suffering coughing, breathing difficulties and a temperature. But MERS differs in that it also causes rapid kidney failure.