A valve arrangement structure of a control valve unit includes a control valve body to which oil is supplied from a main pump. The valve arrangement structure includes a pressure regulator valve that is arranged in the control valve body and regulates a pressure of discharged oil from the main pump to a line pressure, a pressure control valve that is arranged in the control valve body and regulates the pressure of the oil to a required pressure with the line pressure as a source pressure, and a first oil passage that is provided in the control valve body and connects the main pump and the pressure regulator valve. The pressure control valve is arranged on a second oil passage branched from the first oil passage.