How stem cells are recruited to and maintained in their niches is crucial to understanding their regulation and use in regenerative medicine. Here, we demonstrate that DE-cadherin-mediated cell adhesion is required for anchoring germline stem cells (GSCs) in their niches in the Drosophila ovary. Two major components of this adhesion process, DE-cadherin and Armadillo/β-catenin, accumulate at high levels in the junctions between GSCs and cap cells, one of the niche components. Removal of these proteins from GSCs results in stem cell loss. Furthermore, DE-cadherin is required for recruiting GSCs to their niche. Our study demonstrates that anchorage of GSCs in their niche by DE-cadherin-mediated adhesion is important for stem cell maintenance and function.