The problem is that, in a mobile wireless system, when more than one frequency block composed of resource blocks that are consecutive on a frequency axis is assigned to one mobile station, the multi-diversity effect due to scheduling increases by the number of assigned frequency blocks being increased, but the overhead caused by the scheduling information increases. Accordingly, there is a tradeoff between the multi-diversity effect and the scheduling overhead. However, when the aforementioned tradeoff was considered with OFDM and SC-FDMA, the same fixed number of frequency blocks would have been used for all mobile stations. Accordingly, an optimization that takes into account the tradeoff between the multi-diversity effect and scheduling overhead has not been sufficiently achieved. In a wireless communication system, the maximum frequency block number, which is the maximum number of the aforementioned frequency blocks assigned to the same mobile station, is set based on system information, which is information pertaining to the base station installation environment and the mobile station or the mobile station's communication status, and the base station assigns no more resource blocks than the aforementioned maximum frequency block number.