In a CDMA wireless communication system equipped with a base station, and at least one of wireless communication terminals which performs packet communications with respect to the base station by using at least one carrier, and wireless communication terminals which performs packet communications with respect to the base station by using a plurality of carriers at the same time. The base station includes: allocation information applying unit which applies allocation information which is commonly employed with respect to the plural carriers when a carrier is allocated to a specific terminal of the wireless communication terminals; time slot allocating unit which allocates time slots which are used by the wireless communication terminals in communications; allocation information storage unit which stores thereinto the allocation information; and time slot distribution determining unit which determines a time slot distribution which can be used by both the wireless communication terminals using one carrier, and also, the wireless communication terminals using the plural carriers at the same time.