Base-isolation system is designed to lengthen the period of the building. However, this can also increase wind-induced responses of the structure since wind forces have long duration and predominant energy on long periods. Furthermore, the mean component in the along-wind direction also causes certain base-isolation components, such as sliding bearings to become prone to creep phenomenon. Despite of this, evaluation methods of wind-induced response considering creep property on highrise base-isolated buildings with sliding bearings has not yet been fully investigated. Therefore, this paper examines the evaluation method on those buildings and clarifies the effect of creep property using timehistory analysis.