The former Manchester City and Fulham boss was appointed as the west London club's new manager days after Neil Warnock was sacked.
Hughes joins the Hoops with the club one point and one place above the Premier League relegation zone, with investment essential if they are to retain their place in the top flight.
It is the Welshman's first job since he left Fulham last year citing their lack of ambition and expressed his wish to be involved in the Champions League.
Given Rangers' perilous position, Hughes was forced to deny the job was a stepping stone to something bigger.
Instead, he insisted the ambition of the club matched his and he was looking to the long term without any break clause in his contract.
Hughes told reporters at a press conference: "My last couple of positions haven't lasted as long as I wanted them to, so now I'm wanting longevity.
"I've just had my first day at the training ground - I'm certainly not thinking of leaving any time soon."
Of his departure from Fulham, Hughes added: "The situation at the end of last season is one that has happened.
"I made the decision that was the correct decision and I stand by that.
"This excited me. My thoughts now shouldn't be an issue to them.
"I'm looking forward and really happy with the decision I've made, very excited of what is ahead of us."
Hughes added: "I needed to get all the facts and understand the story QPR hope to have in the future. They are a club who want to go places and build from the bottom up - and that fitted very, very comfortably with where I feel my career needs to go now."
The 48-year-old would not be drawn on his transfer targets, with Manchester City defender Nedum Onuoha and Blackburn defender Chris Samba among those linked to the west London club.
Hughes said: "If there are quality players available and they're attainable, then I'll be delighted - but it's difficult to manage the transfer window carefully."
QPR CEO Philip Beard said: "The decision (to sack Warnock) wasn't taken lightly. You can either stick with what you've got or make a difficult decision to change the manager.
"But we believe this is the right time to make this change... Mark was the person we felt shared our ambition.
"I think every QPR fan will feel we've made the right decision. It won't happen overnight but our ambition matches Mark's.
"When we first made contact, I wasn't sure it was going to be an easy job to persuade someone of Mark's calibre to come to QPR - but we had some exciting discussions and the conversation started getting a lot closer in terms of what we can achieve here."
Asked about speculation that the change of management was made due to player discontent, Beard added: "That's not the reason we made the decision - the club belongs to the fans.
"Neil Warnock got the club to the Premier League for the first time in 15 years. We're passionate about what we want to achieve here and wanted to give Mark the chance to come in. We wanted to strengthen and needed to do it really quickly."
Hughes added: "It was very clear in my mind once I had spoken to Philip and the owners it is a club that matches my ambitions.
"We need to win football matches in the coming months, we'll work really hard to make sure that happens."
Hughes also confirmed he would be given funds to strengthen the squad although he refused to reveal how much.
He did though admit the need to be clinical in front of goal was essential in the Premier League.
He said: "Certain areas need addressing but I'll take my time.
"It is important to recognise the strengths of the group, I need to assess that.
"At Premier League level the ability to take chances and score goals is crucial.
"If I feel we need to strengthen in that area, then we will look to do that."
Joey Barton is the current captain and Hughes insists he has no concerns over the player's use of social media to air his sometimes controversial opinions.
Of his predecessor, Hughes had every sympathy for Warnock.
"Neil has done a fantastic job here.
"He created a great deal of success and has made a huge impact on this club during his time here."