To provide a processor controller in a working machine preventing a log from crashing against a driver seat when performing operation while changing the posture and the position of the gripped log so as to enable safe visual observation.

The processor controller in a working machine is structured as follows: a processor which holds the log to perform a prescribed operation or cut the log, is mounted at the tip end of the arm of the working machine; the processor is provided with a hydraulic motor for turning the body of a working tool, a grapple for grappling the log, a log conveyor 107 for conveying the log grappled with the grapple in a length direction, and a chain saw 106 for cutting the grappled log; and the processor includes a calculation unit 93 for calculating the position of the log after a periodic calculation when activating an actuator to give a desired action to the log grappled with the grapple, and a contact determination means for determining whether or not there is fear that the log comes in contact with the working machine, based on the position of the log after the periodic calculation, and data on a contact determination area which are stored in a storing means 92.