If you can it would be better to put that money into some form of investments that would help you have much more money into retirement than tying up the money you would be paying off your mortgage with.
If you're not into investing and would like to get your mortgage paid off sooner than it could be a good idea to pay your mortgage off early before retirement because then you would only need to pay the property taxes and any other bills and not have a huge mortgage payment hanging over your head.
You could then put that extra money that you were paying on a mortgage into a high yield savings account which could then be a good retirement fund when you do retire.