Hardening of blood vessels has steeply increased every year, and implantation stent was used to solve that the conditions of illness. However, in-stent restenosis continues to make problem. To overcome the problem of in-stent restenosis, the concept of local delivery of antiproliferative or immunosuppressive drugs has been introduced into interventional cardiology. Local drug delivery system was demonstrated by using drug-eluting stents coated with nanoporous anodic aluminum oxide (AAO) used for controlled drug release. Effects of diameter and depth of AAO on the diffusion characteristics of drug were investigated. 2-deoxyadenosine was tested. AAO pore diameter and depth showed image by SEM and characterization of diffusion of drug from the AAO nanoporous pore diameter and depth was carried out using by HPLC (high performance liquid chromatography).