are indicated in terms of the lengths of bars or of the digital type in which the detected values are indicated in terms of digits on the other hand the state change indication marks may also use letters next a second embodiment will be described with reference to fig9 a and 9b in the second embodiment the display device of the working machine according to the invention will be described on a monitor panel which is employed in an arm crane having a hook attached to the bucket portion of the hydraulic shovel with reference to the accompanying drawings fig9 a is a view showing the display screen before switches are depressed and fig9 b is a view showing the display screen after the switches were depressed here the screen construction of the display screen 2 shown in fig1 a and 1b to fig7 is different from that of the display screen 2 shown in fig9 a and 9b of the individual state indication marks shown in fig9 a and 9b the same state indication marks as those shown in fig1 a and 1b to fig7 will be described by designating them by the common reference numerals on the display screen 2 there are displayed the state indication marks.