Janikowski, who led the team in scoring for the 10th campaign in a row when he made 26 of 29 field goal attempts last season, agreed a four-year deal worth $16 million, the newspaper said on its website (www.insidebayarea.com).
"He is the best kicker in the NFL and the Raiders have recognized that fact by rewarding him with this monstrous contract," said the player's agent Paul Healy.
The Raiders confirmed the signing on their website (www.raiders.com) but provided no details of the contract.
Janikowski was one of only two NFL kickers to make six field goals of 50 yards or longer last season including a team record 61-yarder at Cleveland, the third longest all-time in the league, according to Oakland.
(Reporting by Gene Cherry in Salvo, North Carolina, editing by Tony Jimenez)