A radio communication system, a radio station, a network operation management apparatus, and a network optimization method are provided that make it possible to avoid performance degradation in the entire system when network optimization is performed individually. In the radio communication system in which radio stations perform network optimization based on statistical communication quality in at least one cell, a radio station (10) notifies information related to a change in statistical communication quality in a cell under the radio station (10) to another radio station (20) or a network apparatus (30) managing the another radio station.