How do I remove old blood stains on a chef apron?

Peroxide removes blood from fabric.

Hydrogen peroxide, then launder, w bleach if you wish.

Peroxide!

Soak the stain in hydrogen peroxide.

try hydrogen peroxide -- or a good pre-wash stain remover that says 'blood stains .... FRESH blood stains are readily removed by hydrogen peroxide and cold water.

If it has been washed and dried in the dryer, it may take some serious soaking if it will come out. Oxy or peroxide will help. Hot sets blood, so make sure you use only cold water.

HI Cody. Try using hydrogen peroxide. As long as it hasn't set in and been washed it should remove the stain.