Toll-like receptors (TLRs) are a group of proteins involved in recognition of highly conserved microbial structures and endogenous molecules released during tissue damage, which makes them key players in innate immunity. By activating nuclear factor B (NFB), TLRs are also involved in several physiological processes including angiogenesis, apoptosis, and tissue repair. As shown in recent publications, disorder of TLRs signaling pathways as well as abnormalities in their expression may underlie various diseases, such as sepsis, life-threatening infections, tumors. This paper reviews the role of TLRs in innate immune response and consequences of disturbances in their functioning.