Atletico's triumph - their first since 1996 - ended a nine-year spell where only heavyweights Barcelona or Real Madrid won the Liga trophy.
Despite leading the league by as much as six points in April, Diego Simeone's side were made to work until the very last day of the campaign for their 10th Liga title, with a tense 1-1 draw at the second-placed Barcelona.
Barcelona could have won the league themselves with victory, and went 1-0 up through a stunning Alexis Sanchez strike - only for Atletico defender Diego Godin to power home a headed equaliser just after half-time.
Atletico were denied the chance to win the title last week after being held to a nervy 1-1 home draw against Malaga, which followed a 2-0 defeat at Levante.
That forced them to win the league at Camp Nou and that they did, giving them a vital boost ahead of next week's UEFA Champions League final against cross-town rivals Real Madrid in Lisbon.
That Atletico have been able to combine a sustained push for continental silverware alongside a successful league campaign is testament to the season they have had.
Simeone, involved as a player in the club's 1996's success, has implemented an intense, pressing style and that, and the excellence of striker Diego Costa has played a key role in their success.
Costa has netted 36 goals in 51 appearances in all competitions this season, but could be a doubt for the Champions League showpiece after limping off with a hamstring problem at Camp Nou.
Their defence has also been outstanding, conceding just 26 goals, with Chelsea loanee Thibaut Courtois enjoying another excellent campaign in goal.
Atletico's triumph comes in their second full season under Simeone, who succeeded Gregorio Manzano in December 2011.
The champions finished with 28 wins from their 38 league games and were applauded by the home faithful at full-time.
