Most will say that it is not too late, and I agree BUT....
It depends on you and what you want from music. I've been playing for 18years, and after about 9 years, I was still not very good. I'm still dissappointed with my progress, despite uncountable hours of practice.
When I had played about a year, (practicing daily), I met a girl who had been playing 1 day, and was already grabbing 3chord songs, and singing. She was better than I was after one day, still I perservered.
Some people pick up a guitar quickly, like some people pick up second languages quickly, while others live in foreign countries for decades, and still aren't fluent.
My point is this. If I had it to do over again, I wouldn't play the guitar (although, it is part of me now). I'd have played the saxophone. It is much simpler. A mediocre sax player sounds much better than a mediocre guitarist. You can't walk across the street without bumping into a guitarist.
If I had played the sax all this time, I'd be a much better sax player than guitarist.
But you might be one of those people who pick it up right away, don't let me discourage you. I just wanted to give you something to think about.