Does Nikon 28-80mm lens fits on Nikon D3100?

Okay. I want to find out is the Nikon 28-80mm lens can fit on my Nikon d3100?

It will fit, but the question is will it work properly? If its an AF-S lens, yes. If it's an AF lens, then no - it won't meter or autofocus.

There are several different versions of this lens. But all of them are AF, not AF-S, so they will not autofocus on your camera.

Don't listen to the first persons comment.
Yes but it won't auto focus on the D3100.It needs to be used with something like a D7000 which has a built in AF motor. That lens was a cheap kit lens included with lower end film cameras. Its built almost like the 18-55mm kit lens.
However since you have a crop sensor camera it will act like a medium telephoto lens. 28mm is still useful on the D3100 but not as useful as 18mm. You'll probably find yourself taking a couple of steps back even at 28mm.
Edit you should also include the rest of the lenses name. For example the older Nikon 28-80mm f/3.5-5.6 AF-D will work on your body but won't auto focus. The newer AF Nikkor 28-80mm f/3.3-5.6G will work to but it won't auto focus on the D3100.

It will fit if it has a Nikon F-mount. It won't autofocus if it's not an AF-S or AF-I model lens.