A micro-feeding method is studied with a modified table feeder. The table feeder examined has either two or three scrapers, and can feed such small amount of powders as several mg/s. Precision of feeding is tested with particular attention to characteristics of the feeder and properties of powders discharged. Powders used in the experiment are quartz sand, talc, calcium carbonate and others covering a wide range of flowability. Furthermore, with respect to testing methods of a feeder, the effect of sampling period on the precision is studied both experimentally and theoretically. As a result, variation of precision with sampling period becomes clear even when the powder flow rate has a periodic fluctuation.