It depends on the apartment you plan on renting. If you plan on renting a crappier apartment then you might not have to have good credit. But if you plan on renting a newer apartment that is high end then yes you'll most likely require having a good credit rating.
A credit rating for renting an apartment will need to be at least 620 any less than that then you're not likely to get the apartment.
If you have bad credit then you might get an apartment by having a roommate with good credit signing the lease along with you or have someone you know such as your parents cosign the lease.