The results of the relationship between standing crop of Miscanthus sinensis grassland and soil morphological characteristics are as follows. The Miscanthus sinensis grassland seems to grow well in volcainc ash soil. The depth of A layer was closely related to the standing crop of the Miscanthus sinensis grassland. The root systems of Miscanthus sinensis reached to its maximum in A layer. The root systems of Miscanthus sinensis showed its maximum at 20mm and below(soil hardness). The soil texture of A layer showed SL-SiL. The soil structure of A layer contained Massive-Small Granular. The soil colors of A layer expressed Dark Yellowish Orange-Brownish Black.