A method and an apparatus for controlling network access of a User Equipment (UE) based on the network's load and time tolerance (delay tolerance) are provided. A network access method for a terminal in a wireless communication system includes sending an access request message containing a time-tolerant indicator at a predefined time, determining, when a reject message is received, a cause value and a hold time contained in the reject message, and re-sending the access request message after the hold time elapses.