PURPOSE: To achieve desirable machining on inner and outer surfaces of a hole by machining the inside of the hole of a workpiece by electrolytic polishing and chemical polishing along with deburring and then automatically transferring the workpiece in a barrel polishing device for barreling the outer peripheral surface thereof.

CONSTITUTION: After stored in a container to be machined by using an electrolyte or chemical liquid, workpieces conveyed by a workpiece supplying conveyer 55 are put into empty barrel tanks by a conveyer provided above barrel tanks 101, 102, 103. On the other hand, abrasive stones are supplied to a hopper 106 through a return conveyer and an abrasive stone supplying conveyer, and then supplied to any barrel tank as required through an abrasive stone distributing conveyer 107. In case there is no circulation of abrasive stones, they are supplied from an abrasive stone supplying hopper 108. After polishing for a set period of time, covers are removed by a manipulator 110, and the barrel tanks are inverted to select the contents by selectors 111, 112, 113. The finished workpieces fall on a conveyer 114 and are conveyed to a workpiece container 115.