Micro-feeding of a fine powder was experimentally investigated by use of a capillary tube (less than or equal to 1.6 mm in diameter) as an powder exhaust pipe that was vibrated under conditions of less than 760 Hz and 30 mu m in amplitude. It was found that only the particles near the inside wall vibrated at random and almost all of the inner particles were transported downwards as a lump of powder. Particles of 10 mu m in diameter could be discharged continuously at a constant rate as small as 0.2 mg/s and the powder flow rate increased with the vibration frequency. It was also found that the critical frequency for powder discharge was nearly inversely proportional to the square root of the vibration amplitude. However, there was a maximum flow rate that depended on the capillary diameter d and the kinds of powder. The maximum flow rate was found to be proportional to d(n) where n = 2-2.5.