Photodynamic　therapy　(PDT)　is　a　new　technology　using　photodynamic　effect　for　disease　diagnosis　and　treatment.　It　is　a　two-step　technique　involving　the　uptake　of　a　photosensitizer　by　cancer　tissue　followed　by　light　irradiation　that　excites　the　photosensitizer　to　produce　highly　reactive　oxygen　species,　the　latter　execute　apoptosis　of　cancerous　cells.　As　a　second-generation　of　photosensitizers,　phthalocyanine　demonstrates　higher　absorption　in　the　650-800nm　range　and　short　tissue　accumulation　compared　to　their　first　generation.　However,　many　potent　phthalocyanine　photosensitizers　are　hydrophobic　and　poorly　water-soluble,　which　limit　their　therapeutic　applications.　As　a　result,　advanced　delivery　systems　and　different　strategies　are　called　for　to　improve　the　effectiveness　of　PDT.　Facts　have　proved　that　using　nanoparticles　as　carries　of　photosensitizers　is　a　very　promising　route.　Nanoparticles　have　the　potentials　to　increase　photosensitizers＇　aqueous　solubility,　bioavailability　and　stability,　and　deliver　photosensitizers　to　the　target　tissues.　This　article　reviewed　the　commonly-used　nanoparticles,　including　colloid　gold,　quantum　dots,　paramagnetic　nanoparticles,　silica-based　materials,　polymer-based　nanoparticles,　as　potential　delivery　systems　for　phthalocyanine　photosensitizers,　and　summarized　the　improved　biological　functions　of　phthalocyanine　photosensitizers　in　PDT.　©　2012　Bentham　Science　Publishers.