Coach Luis Enrique says Barcelona are already focusing on completing the treble after sealing the Spanish title.
The Catalans beat Atletico Madrid 1-0 to ensure rivals Real Madrid cannot catch them at the top of La Liga.
Barcelona face Athletic Bilbao in the Copa del Rey final on 30 May before the Champions League final against Juventus on 6 June.
"We have two more titles to win but we have picked up the one for consistency," said Enrique, 45.
It means former Barca midfielder Enrique, who replaced Tata Martino last summer, has the chance to emulate Pep Guardiola by winning three major trophies in his first season.
Barca 'don't understand transition'
Enrique experienced challenges off the pitch during his first few months in the role, facing criticism in January for leaving Lionel Messi and Neymar on the bench as Barca lost to Real Sociedad to leave Real Madrid in control of the title race.
"We started 10 months ago with many changes at the club which doesn't understand the idea of transition and was coming off a season having not won anything," said Enrique, who was also reported to have fallen out with star man Messi during training in January.
"There is no way that a trainer of a top club will not receive criticism during the year and I knew that.
"We knew that we wouldn't be given time but we did our best."
Barca building on Guardiola glory
After last season ended without trophy, midfielder Sergio Busquets says the club are continuing the success started by Guardiola in 2008-09.
"La Liga is the most important - we play against everyone home and away," Busquets said.
"The Champions League is more prestigious but this is more important. Last year we struggled a lot, we weren't at the right level to be champions.
"You can't win every year but there is no end to this cycle. We are a very young team - this is an historic day.
"This winning era hadn't ended. What Pep Guardiola started with [Lionel] Messi, Xavi, [Andres] Iniesta is still going. We have one title now and are two more wins away from a historic season."
|Nine of Barcelona's 23 titles have been won by a coach during their debut season|
|James Bellamy (1928-29)||Helenio Herrrera (1958-59)||Pep Guardiola (2008-09)|
|Josep Samitier (1944-45)||Terry Venables (1984-85)||Tito Vilanova (2012-13)|
|Enrique Fernandez (1947-48)||Louis van Gaal (1997-98)||Luis Enrique (2014-15)|
Ancelotti rues 'difficult' second half of season
Real Madrid won 13 successive La Liga matches to lead the Spanish top-flight going into the winter break, but four defeats since the season restarted in January - plus two home draws against Villarreal and Valencia - have proved costly.
Their hopes of becoming the first side to retain the Champions League were also ended by last week's semi-final defeat by Juventus.
"The overall assessment of the season is not positive because Real Madrid play to win and we haven't managed it," said manager Carlo Ancelotti.
"We had a good first half to the season but the second half was more difficult.
"The team reacted well and had a very good attitude. It was not easy to motivate the players after Wednesday and I am grateful. Now we have to prepare professionally for the last game right up until the last minute. We have to keep our heads held high, although the team has not won, they have battled."
'Unlucky' Real congratulate Barca
Real Madrid's hopes of only a second Spanish title in seven seasons were hampered by injuries to key players including Luka Modric, James Rodriguez and Gareth Bale over the course of the season.
And Barca were left needing just a win for the title after Los Merengues hit the woodwork three times, with Cristiano Ronaldo missing a penalty, as they drew with Valencia last weekend.
"There were key moments during the season in which we weren't able to pick up vital points and we lacked a bit of luck at times," said Madrid defender Raphael Varane.
"We have to congratulate the champions because they have done very well. We'll try to win it next year."