PURPOSE: To stabilize the feeling of the seating by enabling the lifting and lowering of a driver's seat and a foothold of a maneuvering part in a working car while keeping the state of the relative positional relation constant.

CONSTITUTION: The objective maneuvering part of a working car has a construction characterized by installing a panel 2, a driver's seat 3 having the integral operation panel 2 near its lateral side, a means 5 for lifting and lowering the driver's seat 3 relatively to a car body 4, a foothold 6 of the maneuvering part located under the front side of the maneuvering seat 3 and a means 7 for lifting and lowering the foothold for lifting and lowering the foothold 6 of the maneuvering part relatively to the car body 4 and further a means 8 for performing the lifting and lowering operation capable of synchronously operating the means 5 for lifting and lowering the driver's seat with the means 7 for lifting and lowering the foothold of the maneuvering part.