PURPOSE: To provide a horizontal fully automatic centrifugal fluid barrel working device which exhibits excellent workability without deteriorating a working environment.

CONSTITUTION: When both disc parts 3, 4 are rotated with a revolution shaft 2 journalled approximately horizontally (for example, inclined at 20 degrees at most from the horizontal line), a planet motion mechanism built in the disc part, 4 rotates and revolves a rotation shaft at the same time while setting the revolution shaft 2 as the center. Rotation clamping mechanisms (a part of a barrel clamping mechanism) 5, 6 mounted in the rotation shaft clamp a sealed cylindrical barrel so as to rotate it. A hydraulic cylinder (the rest of the barrel clamping mechanism) 8 works on the rotation clamping mechanism 6 so as to release clasping of a barrel 7. A barrel handling mechanism conveys out the barrel released from clamping to the outside of a device and sets the next unworked barrel.