A driving control device for a vehicle device , which has an operation lever device for outputting a signal to instruct a travelling speed and a traveling direction of a vehicle by tilting a single operation lever forward, backward, left and right, and a hydraulic motor controller for controlling rotation speeds of two hydraulic motors for driving respective traveling devices on left and right sides of the vehicle body according to the signal from the operation lever device, and which controls the traveling of the vehicle device by operating the operation lever of the operation lever device, has a spin turn instruction member which outputs a signal to make the two hydraulic motors have the same rotation speed but in different rotation directions from each other by rotating the operation lever of the operation lever device.