AF-S NIKKOR 300mm f2.8G using in Nikon D5100? - 1

Can I able to use Nikkor 300mm FX single focal length lense in DX Nikon D5100? What are the disadvanges?

Of course you can. It's a big, heavy lens with a limited angle-of-view.

When you need something this powerful, though, there's no substitute.

It is the perfect lens for shooting sports or wildlife in low light conditions.

Here is a sample shot using that lens on a D300. The extra reach you get using a camera with an APS-C sensor is what makes this lens and your camera a good match.

Remember if you use a tripod or monopod to mount it to the lens, NOT the camera.

Yes. This disadvantage is you can't hand hold it.