In July, 1966,twelve stations in Sarobetsu moor, being different in floral composition or soil type, were selected and two soil samples (each sample : 10×10×10cm) per station were collected. The samples were dried in improved TULLGREN apparatus to extract soil mites. Of a total of 449 mites, 342 individuals belonged to oribatid mites (30 species). The species peculiar to each type of vegetation were as follows : Trhypochthonius sp., Tectocepheus velatus (MICH.), Quadroppia quadricarinata (MICH.) and Zygoribatula sp., to the moor ; Carabodes sp. to the thicket of Sasa paniculata MAKINO ; Tegoribatidae sp. to the forest of Quereus dentata THUNB.; Eohypochthonius gracilis crassisetiger AOKI, Damaeidae sp. and Liacarus orthogonius AOKI to the ecotone ; Palaeacaridae sp. to the potato farm. None of oribatid mites, however, could be found in the grassland. Of all the oribatid mites Oppia sp. was the most predominant (23.6 per cent.) Tectocepheus velatus (MICH.) was found at the same station both in soil and on plants, Phragmites communis TRINIUS, Sium nipponicum MAXIM, and Rubus chamaemorus L.