How can I get rid of smell in ski boots?

The best thing you can do to get rid of the smell in ski boots is to completely dry out your boots after every time you ski with a boot dryer like the Hotronic Snapdry Boot and Glove Dryer. You may want to take the boot liners out of the shells to really dry out the liners, and also fully dry out the wet interior plastic boot shell, but it may not be necessary after every ski day.

It's also very important to change into a clean pair of dry merino wool ski socks when you get to the mountain before heading out to ski. This is due to the fact that the socks you wore while driving to the mountain will be sweaty from the drive and being in shoes, which will add unnecessary funk and cold to your ski boots.

You can also use Odor-Eaters Foot & Sneaker Spray Powder in the liners. To help keep your feet from sweating, try using a foot powder like Gold Bond Medicated Foot Powder. 

You can also try and kill bacteria in the ski boot liner by freezing the liners, either outside for 24 to 48 hours or stick them in your freezer.