It has been observed from the previous investigation that the flow structure in the main channel changes and sediment transport rate decreases for meandering compound flow compared to bank-full flow. Because of this characteristics of the meandering compound channel flow, we have considered over loading sediment supply due to dam or bank failure in the channel that might cause large bed level fluctuation. In this paper, we have investigated the mechanism of bed level change for compound meandering channel experiment using steady flow and overloading sediment supply. The parameters for meandering compound channel bed fluctuation of this study include over loading sediment supply, planform of the channel and changes of relative depth. Additionally, we also have examined the characteristics of bed topography during flood period with unsteady flow condition.