In cancer treatment, minimally invasive therapy such as photodynamic therapy (PDT), currently being applied in clinics, allows highly localized treatment by the use of focalized light on the tumor area. Moreover PDT is indicated for small size solid tumors for which heavy surgery or chemotherapy is not justified. However, persistent limitation for PDT is the low specificity of the photosensitizing agent for the tumor, with poor delivery at inadequate concentrations to the treatment area causing irreversible side-effects. Porous silicon (pSi) nanoparticles are attractive materials for the design of applicable nanotherapeutics, as they are biodegradable in vivo. Made from semiconductor silicon, pSi also exhibits intrinsic photoluminescence when excited in the visible and near infrared, which is very amenable for in vivo imaging, under both one and two photon excitation^. Here we will present the high potential of biodegradable pSi nanoparticles functionalized with photosensitizers and targeting agents for one and two photon photodynamic therapy.