Non-vascular epiphytes are known for the diverse roles they play in ecosystems, which include providing habitat for organisms and participating in nutrient cycling. These epiphytes are biological indicators due to their sensibility to environmental conditions and their rapid life cycle and, in a climate change scenario, they may be the first to suffer from the effects of higher temperatures and changes in precipitation patterns. The objective of this work was to evaluate the potential that the non-vascular epiphytes have to store water in Tropical Forests. The study was carried out in areas of Montane Atlantic Forest located in the Serra do Mar State Park, characterized by the abundance of vascular and non-vascular epiphytes. We used 5 permanent plots of 1ha each, established by the BIOTA/FAPESP Functional Gradient Project - 3ha of old growth forest, 1ha subjected to selective logging, and 1ha of late succession forest - areas in which the biomass of non-vascular epiphytes was estimated using an allometric model developed by the author herself. The amount of water present in the wet biomass of non-vascular epiphytes was calculated from this estimated dry biomass,. Mature forests stored between 913.4L and 1330.7L of water per hectare in non-vascular epiphytes, in the forest where there was selective logging the stock was 530.9 L/ha and 703.8 L/ha in the late successional area. The non-vascular epiphytes that occur in understory trees store approximately 50% of the total water stocked by epiphytes in each area. Our results show that the non-vascular epiphytes store a large amount of water, creating a wet microhabitat in the tree trunks, which is strongly affected by the disturbance