The present invention relates to an adjusting device of wafer machine, which includes a rotary adjustment assembly that is rotatable to cause the rotation of a rod so as to displace a support block thereby elevating or lowering a support post. A balance board is thus caused to move a wafer substrate so as to realize balancing of wafer through the support post, whereby efficient adjustment of the wafer machine to a balanced position can be achieved without extra expense of time in adjustment operation and thus accelerating the time of manufacturing process and providing extremely high precision and further effectively reducing the potential risk of damage caused by over-adjustment.