PURPOSE: To automatically perform the polishing, washing and selection of media in an efficient manner, by using an electric control panel and some automatic control boxes commensurate to the number of barrel polishing tubs, in plural rotary barrel polishing tubs.

CONSTITUTION: Works subject to an abrasive stored inside a box 30 are discharged into a bucket 32, fed to a feeder 28 via an injection tub 36 after being mixed with media, then stored in the bucket of an injection device 42 and discharged into a chute 44. At this time, using a cylinder 46, works and media inside the chute 44 are forcibly pressed and housed inside a barrel abrasive tub 48 through an on-off port 49 of the tub 48 whereby washing after polishing is fed to the inside of the tub 48. Next, a cover of the tub 48 is manually closed, then an automatic control box 50 connected to the tub 48 is operated, automatically performing a washing motion, and when this washing is over, a traveling table 21 is transferred onto a rail 17, then positioned at the lower side of the tub 48 and selection of the media takes place.