The Reds had been strongly tipped to secure 2007/08 Premier League glory, but Rafa Benitez's side ended the campaign in fourth position and 11 points adrift of champions Manchester United.
"We say it every season, but it's massive," Gerrard told the Liverpool Echo. "Other teams are going to strengthen and become better sides so it's important we do the same.
"A lot of sides spend every summer, teams and squads become stronger and it's important we don't fall away.
"We want to stay up there with the best and for us to challenge and win the league and to keep doing well in Europe we need to buy players, there's no doubt about it."
Gerrard, though, admits he is in the dark over Benitez's close-season targets.
"I know as much as the other players and you guys outside about Rafa's plans," Gerrard added.
"He doesn't call me in and tell me names, but obviously he assures me and the rest of the boys that if any players become available that will strengthen the team he will go and buy them, but it's important that Rafa gets the right backing.
"It (a title tilt) is getting down to the small details again so if we can make the team that little bit stronger, have a few more options and a few more match-winners and be a tiny bit better defensively as a team then we can do it."