To provide a drive control unit which can control the drive of an actuator of construction machinery in such a manner that operating characteristics vary depending on an operation speed of an operation means.

This drive control unit for controlling the drive of the actuator of the construction machinery is characterized by determining a target value of output of the actuator on the basis of a manipulated variable input into the operation means of the construction machinery, and a rate of variation of the manipulated variable. The actuator is an electric motor for driving at least either a swing mechanism of a revolving super structure of the construction machinery or a traveling mechanism of an undercarriage of the construction machinery. The output of the actuator is controlled by controlling an electric current applied to the electric motor.