An apparatus and a method of controlling slot-based channel access by an access point (AP) to manage a network in a wireless local area network (WLAN) environment and a slot-based channel access terminal are disclosed. A slot-based channel access control apparatus of a WLAN system according to an exemplary embodiment determines one of each terminal and a group of terminals as a slot allocation target, allocates a slot defined in a beacon interval to the determined terminal or group to distinguish channel access time, and transmits a beacon including information on the allocated slot.