The cash-strapped Second Division side from Limburg Province joins a portfolio of clubs that consists of Manchester City and stakes in New York City FC, Melbourne City, Yokohama F. Marinos, Montevideo City Torque, Girona, Sichuan Jiuniu and Mumbai City.
Lommel is the ninth club in Manchester City's parent company global portfolio.
Lommel has debts reported to be in excess of 2 million euro. These are to be settled as part of the deal.
The City Football Group now has full or part ownership of clubs in three European countries and in countries in four other continents.