The opener of the 29-day tournament will start at 1600 GMT at the 60,000-capacity Al Bayt Stadium in the city of Al Khor, 35 kilometers (21.7 miles) north of Doha.
Ecuador's national team has played three FIFA tournaments, but Qatar are making their debut because the host country qualifies automatically.
While Ecuador will be expecting goals from their scorers Enner Valencia, Moises Caicedo and Pervis Estupinan; Al-Sadd winger Akram Afif and Al-Duhail forward Almoez Ali will be Qatar's trump cards in the World Cup.
Qatar are placed in Group A with Ecuador, Senegal, and the Netherlands.
The event will conclude with the final match at the 80,000-capacity Lusail Iconic Stadium on Dec. 18.
Source: Anadolu Agency