The ability of manual paper feeders to cope with increasing types of paper sheets (particularly basis weights) is approaching its limit. In this invention, when an operator performs a simple operation of, e.g., selecting the type of paper sheet on an operation panel, paper feed mechanism conditions at a manual paper feed port are optimized. That is, a manual paper feed tray desirably capable of being accommodated in a main body automatically changes its position and angle with respect to the main body in accordance with external inputs from an operator, thereby changing the paper feed mechanism conditions. This allows stable paper feed/conveyance of a variety of types of paper sheets and realizes space saving and low cost.