Head and neck squamous cell carcinoma represents the sixth most common cancer in the world, while patients' survival and therapy outcome remain unsatisfying. In recent studies Toll-like receptors (TLRs) have been found in these and various other human tumor cells. TLRs enable their host to recognize a series of molecular motifs derived from pathogens (PAMPs) by activating innate and adaptive immune responses. TLR3 is an intracellular protein receptor that binds double-stranded RNA (dsRNA). It has been reported that the functional TLR3 is expressed in pharyngeal metastatic tumor cells and its activation drives them to apoptosis. Therefore, in this study we tested the effect of individual and combined application of TLR3 ligand, poly(I:C), with antitumor drug cisplatin and γ- irradiation on survival and cell cycle regulation of larynx carcinoma cells. In this study we used SQ20B cell line stably transfected with control shRNA and shRNA for TLR3. Thus we obtained cells with functional TLR3 and cells with silenced gene for TLR3. Results from colony forming assay show that poly(I:C) reduces survival of larynx carcinoma cells by approximately 50 %, while cells with TLR3 knock-down show greater resistance and survival after cytotoxic treatment. Combined therapy proved to be too strong, and requires dose reduction. Cell cycle distribution was analyzed after cell staining with propidium iodide using a flow cytometer. Poly(I:C) increased the arrest of SQ20B cells with functional TLR3 in phases G2/M of the cell cycle, while cell cycle distribution of cells with TLR3 knockdown was similar to control. Cisplatin masks the effect of poly(I:C) in most cases when applied in combination. The results of this study demonstrate how the combination of poly(I:C), cisplatin and γ-radiation could be used in the treatment of patients with tumors that express functional TLR3. This allows the usage of lower doses of drugs and radiation for maximizing the antitumor effect while limiting their toxicities. However, further investigation on molecular mechanisms of the observed effects is required before final conclusions.