Can I put topsoil over grass?

Excuse me, but I was wondering if you could shed some light on a gardening-related query I have. Specifically, I'm considering adding topsoil to my lawn area, but I'm not sure if it's advisable to lay it directly over the existing grass. Would doing so potentially harm the grass or compromise the overall health of my lawn? Is there a recommended approach for incorporating topsoil into an already established grassy area? Your insights would be greatly appreciated.