A suction position adjustment device of a component mounter which includes a head having multiple pickup members and that executes simultaneous suction control for substantially simultaneously picking up multiple components with the multiple pickup members by moving the head to a target position that is determined to locate the multiple pickup members on the multiple components supplied from multiple feeders to a supply position. The suction position adjustment device includes an imaging device configured to image the supply position of the feeder from above, a display device, and a control device. The control device configured to control the imaging device so that an upper surface, at the supply position, in the multiple feeders of adjustment targets is captured and display, on the display device, captured multiple upper surface images and multiple pointers superimposed on the multiple upper surface images, when the target position is adjusted.