The colorimetric aniline method for the determination of pentoses of Tracey^[3] was applied to the hydrolyzates of soil. Experimental tests showed no interfering substances in the color development after the treatment of hydrolyzates with CaCO₃ and cation exchange resin. Equimolar quantities of various pentoses do not give exact equal effects on color development. Since the pattern of pentoses probably is similar in different soils, the aniline method may give an approximate value of the total pentoses content of soils.