The New Light of Myanmar" newspaper reports that Hor Namhong had talks with Foreign Minister U Nyan Win in the administrative capital, Naypyidaw, on Monday.
The newspaper said Hor Namhong visited the gems museum in Rangoon before heading to Naypyidaw.
Cambodia and Burma are members of the Association of Southeast Asian Nations, which has called on Burma's military government to enact democratic reforms and improve its human rights record.
The Cambodian government has not openly called for Burma to reform, but a group of lawmakers formed a special caucus last year to call for Burma's military government to make faster progress toward democracy.