Abstract: A pharmaceutical preparation has a ligand structure specifically recognizing a target site and an amphiphilic compound having a hydrophobic or amphiphilic group. The pharmaceutical preparation employs an amphiphilic compound of specific structure obtained by introducing a chained hydrophilic group with an appropriate flexibility, and thus becomes a fine particle suited for drug targeting. The pharmaceutical preparation is expected to give a prolonged pharmacological effect. A particulate preparation exhibiting a remarkable site targeting property can be formed. Further, according to the selection of matrix forming material, the drug releasing property can be controlled.