Can a 17 year old date anyone over the age of 18 in the state of Illinois?

Dating is not against the law, but sexual activity may be.

Depends on what your parents say about it. They are the law for under 18 year olds.

Well, it is legal for you two to hang out but sexual intercourse is illegal cause that would be seen as statutory rape.. its annoying I know. I once had a thing for a 19 year old.