You bet.
He should give you reasonable notice that he is going to enter (like maybe 24 hours).
Judges take a very dim view of tenants that try to frustrate the landlord's right to show the apartment. They take the dim view of landlords that try to enter whenever they want without warning, but they also know that the landlord's interest is in trying to find another tenant and he must show it in order to rent it out, so cooperate with the landlord. It's in your interest, too, for the landlord to find another tenant. He'll be happier and be more cooperative with your needs as you move out.
Everything works two ways, you know.