Abstract: The present invention relates to a process of preparing a water-soluble complex of water-insoluble or sparingly-soluble organic medicines and beta-cyclodextrin derivatives: a. dissolving successively or simultaneously the organic medicines and the beta-cyclodextrin derivatives in organic solvent(s) at certain mole ratio or mass ratio in the presence of suitable amount of water; b. removing the organic solvent from the solution of the step a to obtain aqueous solution of the organic medicine and beta-cyclodextrin derivative; and c. removing water from the aqueous solution to obtain the complex of the organic medicine and beta-cyclodextrin derivative. The invention also provides a sterile water-soluble complex of water-insoluble or sparingly-soluble organic medicines and beta-cyclodextrin derivatives. A fully-water-soluble complex can be prepared from any water-insoluble or sparingly-soluble organic medicines or other organic compounds according to the present invention.