Background: Hedgehog signaling pathway is a developmental pathway mostly inactive in adult tissues, with the exception of stem cells. It is often found upregulated in various tumors, and associated with cancer stem cell maintenance.Methods: This review focuses on different aspects of Hedgehog activation in tumors, with special emphasis on ovarian tumors and their treatment. Results: Mutations in pathway components lead to a series of developmental malformations and syndromes. Aberrant activation of the pathway can be caused by mutations, noncanonical transcriptional regulation, or epigenetic changes. Conclusion: This pathway is an interesting target in cancer therapy, especially when combined with therapies targeting other signaling pathways. Combination therapy can be used to bypass resistance or to target cancer stem cells in a more efficient way.