Parenting styles

Me and my husband always fight when he disciplines the children.
He yells at them, tells them they are bad kids and spanks them. When he does that I think he is emotionally hurting my kids, they are going to have a rough relationship… etc. I feel annoyed and angry towards him because he knows I hate when he does it. I don’t care what he does most of the time but when it deals with the kids I get super concerned and worried for our kids well being and relationship with him.
What do I do?