The deal, worth EUR1.5million ($1.48m), sees Galp, the national energy company for oil and gas, become the Portuguese league's title backer.
Galp beat off competition from a number of other companies including Vodafone, beer brand Sagres, and Portugal Telecom to win the sponsorship rights.
Galp, which aims to float on the Lisbon Stock Exchange by the first quarter of 2003, will use renowned Portuguese player Luis Figo to promote its sponsorship despite the fact that the player plies his trade for Real Madrid in Spain.
Portugal's domestic soccer league has been boosted by a lucrative new title sponsorship agreement.
