OBJECTIVE To study the preparation of bovine serum albumin nanoparticles surface-modified with glycyrrhizin(BSA-NP-GL) targeting to hepatocytes. METHODS The bovine serum albumin nanoparticles (BSA-NP) were prepared by desolvation process. Glycyrrhizin (GL) was oxidized by sodium periodate to be conjugated to surface reactive amino groups (SRAG) of the BSA-NP. The SRAG were quantified by spectrophotometric method using 2, 4, 6-trinitrobenzenesulfonic acid(TNBS). Glycyrrhetinic acid(GA) hydrolyzed from GL, which was on the surface of BSA-NP-GL was assayed by HPLC after isolation by sephadex G-50. Both methods were used to verify the conjugation achieved. HPLC was used to determine surface density of GL on BSA-NP-GL. RESULTS The amount of SRAG of the BSA-NP-GL decreased by 19.6% compared with normal BSA-NP. The amount of GL molecule was 9.2% of the total determined SRAG of BSA-NP. The mean diameter of the BSA-NP-GL was 73 nm with round shape. The stability of BSA-NP-GL was constant when it was stored at 25 degrees C and 37 degrees C during 10 days. CONCLUSIONS BSA-NP-GL was successfully prepared, which is considered to establish an experimental foundation for further research on its ability for targeting to hepatocytes.