The Hedgehog (Hh) signaling pathway, which was identified for the first time in the common fruit fly, is a highly preserved evolutionary pathway of signal transmission from the cell membrane to the cell nucleus. The Hh signaling pathway plays an important role in the embryonic development. It has a biological influence through a signal cascade culminating in a change of balance between activated (GliA) and repression forms (GliR) of Gli transcription factors. The components of the Hh signaling pathway involved in the information transfer to the Gli transcription factors are: Hh ligands (Shh, IHh i DHh), Ptch receptor (Ptch1, Ptch2), Smo coreceptor, Sufu, Kif7, PKA and cAMP. GliA travels to the nucleus and stimulates the transcription of target genes by binding to their promoters. The main target genes of the Hh signaling pathway are Ptch1, Ptch2 and Gli1. The malfunction of the Hh signaling pathway is associated with the developmental anomalies and tumors, such as Gorlin syndrome, basal cell carcinoma, medulloblastoma, and pancreatic, breast, colon, and ovarian cancer as well as small-cell lung carcinoma etc. The aberrant activation of the Hh signaling pathway is either caused by mutations in the signal pathway (ligand independent signaling) or by the excessive expression of the Hh signaling pathway (ligand dependent signaling-autocrine or paracrine). Numerous Hh pathway inhibitors, like vismodegib and sonidegib, have been developed for cancer treatment. They are regarded as a promising treatment to be used in cancer therapy, especially for patients with a poor prognosis.