On top of a fee paid for a basic cable TV package, fans in Portugal will have to pay some 10 euros (£8.70) per month to watch the Lisbon club's matches played at the Luz stadium on television.
Club President Luis Filipe Vieira hailed the initiative as "historic" and said the deal meant that "Benfica became the first club in the world to fully exploit its TV rights".
Fans can subscribe to the channel through the country's two largest cable operators: Portugal Telecom and Zon. Angolan cable operator Zap will also offer it.
A club spokesman said Benfica were the first big European club to screen league games on their own pay TV channel.
Earlier this year, Benfica reached a deal with the English Premier League for exclusive screening rights in Portugal of the competition over the next three seasons.
Until now, some 70 percent of the broadcasting rights revenues estimated at 75 million euros (£64.2m) per season have gone to the "big-three" football clubs - Benfica, Sporting and Porto.
As in neighbouring Spain, television contracts in Portugal are negotiated on a club-by-club basis, unlike in the English Premier League and Italy's Serie A, where collective bargaining deals are struck.