Yes. The meanings are interchangeable, but they all have a formal tone and would sound a little bit old-fashioned in casual conversation. I would suggest (depending on your intended meaning): Leave him alone. / Don't bother him. Leave it alone. / Leave it there. / Don't touch it.

"Leave him be" and "leave it be" are common expressions. Strictly speaking though, they are only borderline correct. "Let" is a verb that can be followed by just about any infinitive without "to", e.g. "let her swim". "Leave" is not such a verb. I would never say "leave her swim". Instead, I would say "leave her to swim". However, with "to be" the rule is broken so often that it actually sounds good.