You can try to get cat pee stains out of shoes by using a mixture of dish soap and hydrogen peroxide. First, blot the stain with a towel to absorb as much of the urine as possible. Then, mix together 1 cup of dish soap with 3 cups of hydrogen peroxide and apply it to the stain. Let it soak in for about an hour before scrubbing it with a toothbrush or rag. Finally, rinse the shoes off with water and let them dry.