Photodynamic therapy (PDT) belongs in perspective modalities of cancer treatment. It is based on the tumour-selective accumulation of a photosensitizer followed by irradiation with light of a specific wavelength. PDT is widely developed nowadays due to its high specificity and selectivity along with absence of the unadvisable side-effects. Sonodynamic therapy (SDT) exploits ultrasound to induce cytotoxic effect of sensitizer. In our study we tested the possibility of combination of this therapies and icrease of efficiency. Our results suggest that irradiation in combination with application of therapeutic ultrasound increases production of reactive oxygen species and reduces viability of tumour MCF7 cells, compared to irradiation of ZnTPPS4...