Chelsea finished in third spot in the table after ending the campaign with a 2-1 win at relegated Cardiff City.
It is the first time since 2003 that Mourinho has finished outside the top two with whatever club he has been at and means he ends up with no silverware in his first season back at Stamford Bridge.
Mourinho is not too downbeat about finishing third as he feels with the right buys Chelsea will be title challengers from the first day of next season.
"Next season if we do our work in a successful way in the summer market, which I know the club is trying to do everything to make that a successful period for us, then if we do that I want to start day one saying we are going to fight for the title," said Mourinho.
"We don't need a new spine, a new structure. It is there.
"The fundamental for us now is a couple of players of a certain level to help the team immediately go to a different level.
"After that the additional is if someone has to leave then someone has to come. Our work in the summer is not a big amount of work, it is just the right choice."
There is some debate whether Fernando Torres will be part of those plans after the Spain striker struck against Cardiff.
Torres has reportedly become one of Inter Milan's top summer transfer targets and the 30-year-old - who cost Chelsea £50m three-and-a-half years ago - has only two years left on his Stamford Bridge contract.
But when asked if he intended to keep Torres after the win at the Cardiff City Stadium, Mourinho maintained he is happy with his efforts even though Sunday's strike was only his fifth in the Premier League all season.
"Yes, he's in my plans," Mourinho told Sky Sports. "He's a good player.
"I keep saying the same - Fernando is not the kind of player that with half a chance, he scores a goal. He's not the kind of guy that's going to score goal after goal. But the way he works, the way he moves, the work he contributes for the team... he is a player that I like, a player that the club respects and we are happy to have him next season, no problem."
Mourinho repeated that he does intend to bolster his attacking options in the summer, but that does not necessarily mean he is looking to move anyone on.
"I keep saying the same - yes," added the Blues boss, when asked if he was looking to recruit a new forward. "I think everyone knows.
"Samuel Eto'o was here with only a one-year contract -a different situation than Fernando and Demba (Ba). Of course, we want to bring a new striker in for next season, but the players we have are (under) contract.
"And the way Nando and Demba are, they understand what Chelsea is, what the team ethic is and the way they work for the team when they are on the pitch. They are players we are happy to keep."
Ashley Cole was made captain for the day at Chelsea, and Mourinho could not say what the future holds for the 33-year-old left-back, who has been with the Blues since summer 2006.
"Let's see what happens now," he continued when asked about Cole being skipper. "It's time for that.
"No Lampard today, no Terry, so he (Cole) was the player with more time at Chelsea. And I think he's the kind of guy that when he has the armband, Chelsea supporters are happy to see him with it."