Sustained release hydroxycamptothecin polybutylcyanoacrylate nanoparticles (HCPT-PBCA-NP) associated with polybutylpyrolidone (PVP) for liver targeting were prepared by the adsorption-entrapping method. The morphology, sizes, drug loading efficiencies, release characteristics in vitro, distribution and pharmacokinetic parameters in vivo of the HCPT-PBCA-NP associated with PVP were studied. The median diameter of the particles was 81 nm and the drug loading was 1.2%. The release characteristics in vitro were in accordance with the Higuchi equation: Q = 0.0615 + 0.0940 mean square root t. 64.5% of the HCPT were concentrated in the liver at 15 min after i.v. administration of HCPT-PBCA-NP associated with PVP. The plasma drug concentration-time curve of the HCPT in rabbits was fitted to a two-compartment open model. The Vc, T 1/2 and CL were 3.5L; 147h; 0.18L x h(-1), respectively. The method of preparation presented in this paper seems to bean alternative for the preparation of PBCA-NP of poorly soluble drugs both in water and in lipid.