The Elland Road club have slipped from top spot in the Championship to tenth following seven defeats in nine league outings.
Owner Andrea Radrizzani set Christiansen a target of finishing in the top six so the pressure is on the Dane to spark a revival in fortunes.
Kinnear, however, believes the United head coach remains the man to lead the push for promotion.
“I don’t think it is fair to question him,” said the club’s managing director. “Most supporters, fair-minded supporters, would look at a manager coming into a completely new league – a very challenging league, and working with a new squad with new players – and to be three points off the play-offs now is not far off what you would expect a new manager to do.
“In what we have seen at Thorp Arch and in a number of performances, there’s plenty to suggest that Thomas has absolutely the potential to deliver in this league.”
Kinnear’s words of support will, no doubt, be welcomed by Christiansen, who was a surprise appointment following the departure of Garry Monk during the summer.
The Leeds head coach, however, will recognise that life is unlikely to get any easier in the next fortnight or so as Sunday’s televised home clash with Monk’s Middlesbrough is followed by tough trips to leaders Wolverhampton Wanderers and bogey side Barnsley.
A resurgent Aston Villa then round off a tough period for United with a December 1 visit to Elland Road.
Kinnear added: “Naturally, there is concern because we need to stay in touch with the play-off places but we are confident the ingredients are there to regain the form and get back on track.
“The position we are in is not way off track from where we want to be, three points off the play-offs.
“Our target is to get in the play-offs and we are well on track to deliver that.
“I think we have demonstrated that we can beat any team in the division when the team play as they can. I think it is form.”