Can I use lens cleaner and a cloth to clean my 5Ds LCD screen without damaging it?

Yes. The screen is glass and very durable. I've also read that if you did damage it, it's only around $25 to replace the protective glass screen.

Thank you very much Mitchell.

I'm surprised it took so long for people to answer. If you want to read more, here's where I got my info from:

Best LCD protector for 5D MarkII - Canon Digital Photography Forums (http://photography-on-the.net/forum/showthread.php?t=873292)

lol! I just use the inside of my shirt to clean it and it looks like new again. I don't sweat about it much because my lousy sweaty face will be on it again and again. :)