What You Need to Clean Pee Out of a Mattress: 1 bottle of diluted white vinegar. baking soda. a large towel. a vacuum cleaner. Method to Clean Pee Out of a Mattress: Remove all sheets, blankets, any mattress covers, etc. and wash. Blot (don’t scrub!) the urine with a large towel, getting up as much of the liquid as possible. If stains and odors are taking over the mattress in your child’s room, this simple method to remove those nasty pee odors and stains will quickly become your best friend. This is kind of a gross topic to discuss on the blog, but it’s a real life issue that we deal with on a weekly basis. If you need to remove a dry urine stain from a mattress, dampen the area, but do not saturate it. Then, sprinkle borax over the spot and rub it in with your hands. Next, let it air dry before vacuuming up the residue. Finally, return the mattress to the bed. One of my daughters, unfortunately, has an issue with wetting the bed at night. While she’s been potty trained for over a year, and doesn’t wet her bed every night, it’s still regularly happening. Unfortunately this has led to urine stains on her mattress. Multiple urine stains that smell. From an accident caused by your little one to the family pet draining themselves on that brand new duvet, figuring out how to clean urine from a mattress as well as how to get the urine smell out of a mattress can be quite the hassle. To get out the stench of the urine smell you will want to use the vinegar full strength. Spraying the vinegar soak the areas of the mattress that have been affected by the urine. For tough stained area use a toothbrush to rub the vinegar in. Open the windows and run a fan as you let the vinegar set for five to 10-minutes. .