Miss Universe Organization president Paula Shugart, accompanied by Miss Universe 2017 Demi-Leigh Nel-Peters, made the announcement.
Other guests at the Miss Universe press conference were former Miss Universe 1965 Apasra Hongsakula and Miss Universe 2005 Natalie Glebova.
Thailand has already produced two winners – Apasra Hongsakula (1965) and Porntip Nakhirunkanok (1988).
Catriona Gray of Albay, Bicol is the country's representative to the Miss Universe pageant.
Earlier, it was reported that the pageant will be held for the fourth time in the Philippines. Other countries which reportedly bid for the staging of the pageant include Macau and South Korea.
Rumors have it that Gray and other candidates have been chosen to promote the Miss Universe pageant in October.
The Philippines has already produced three winners - Gloria Diaz (1969), Margie Moran (1973) and Pia Wurtzbach (2015).
By TYSON NESSMAN