An apparatus and a method for controlling a moving speed of each bucket and a moving speed ratio between each bucket to be proportional to a degree of operation of each operation indicator (75) and an operation ratio between each operation indicator (75) regardless of changes in various working conditions or load pressures. The apparatus has means for receiving an operation command from an input portion and converting said operation command into an operation signal, means (85) for calculating a required discharge oil amount of a pump (35a,35b) which is proportional to said operation signal and a required moving speed of an actuator (105a,105b) which is proportional to the degree of operation and the operation ratio of said operation signal, means (45a,45b) for adjusting said required discharge oil amount and said required moving speed based on a maximum dischargeable oil amount of said pump (35a35b), means for subsracting a real discharge oil amount and a real moving speed from said adjusted discharge oil amount and said adjusted moving speed, means for controlling the discharge oil amound of said pump (35a,35b) according to the control signal from said substracting means, and means for controlling the moving speed of said actuator according to the control signal from said substracting means.