The hippo pathway is a tumor-suppressor signaling cascade that regulates cellular mechanisms such as proliferation, cell death, cell differentiation and cell migration to ensure a proper development and regeneration of organs. Its function is well studied in Drosophila and vertebrates however, nothing is known about its activity in pre-bilaterians. Hydra belongs to Cnidaria, a sister group of Bilateria, and represents high regenerative capacity. The goal of this work is to study the relevance of the Hippo pathway during homeostasis and regeneration in Hydra. First, we present a wide phylogenetic analysis of 46 gene families related to the pathway. Next, we study the function of the pathway by knocking down several key players during homeostasis and regeneration conditions. Furthermore, we monitor the effect of mechanical tension on the activity of the pathway through its downstream effector YAP.