I'm assuming you are a pretty new keeper? During the shedding process their entire belly turns a light pink color. If that's what you are seeing I would say its shedding. If the pink is only in a particular area then you are probably dealing with a burn or the beginning of scale rot-depending what it looks like. No one can really tell you what is going on without seeing pictures.

First thing I would do is figure out if your snake is shedding or if it's burned. No sense in treating it for a burn if it's just shedding. Also, are you using a heat rock (better known as death rocks), a heat pad, heat tape, heat lamp, etc. That may help to figure out if your snake is getting burned.