A method for the preparation D-chiro-inositol (I) from kasugamycin (II), comprising the steps of: (a) reacting kasugamycin with an acetylating agent to form a crude hexa-acetate intermediate; (b) purifying the crude intermediate to form purified hexa-acetate intermediate; (c) deacetylating the purified intermediate to form D-chiro-inositol; and (d) isolating the D-chiro-inositol. The method permits efficient, large-scale preparation of D-chiro-inositol without the need for extensive chromatographic purification of the final D-chiro-inositol product.