Liverpool did not make public the length of Lallana's new contract, but English media reports he signed a new three-year deal.
Although Liverpool did not make public the length of Lallana's new contract, but British media reports said he had signed a new three-year deal with the option of an extra 12 months.
The 28-year-old Lallana, who arrived at Anfield from Southampton in 2014, told Liverpool's website: "I'm very proud and feel quite humbled by the show of faith from the club and the manager (Jurgen Klopp) in particular."
"Signing for a club like Liverpool is obviously a big thing -- but to re-sign shows you've obviously contributed enough that the people who make the decisions want you to stay longer."
"This is a really good place to be at the moment and, for a player who wants to be part of something special, I can't think of a better club to commit your future to."
Lallana has scored 20 goals in 117 Liverpool appearances to date and follows Philippe Coutinho, who in January signed a new contract to become the club's highest-paid player, in committing his long-term future to Liverpool.
"We have a brilliant squad of players who are only going to get better the longer we are together," Lallana added.