Hematopoietic stem cells (HSCs) are adult stem cells which have the ability to self-renew and to differentiate into cells of the hematopoietic lineage such as red blood cells. In a healthy system, these processes of self-renewal and differentiation are well-balanced, which is only allowed by an organized and greatly specialized microenvironment in the bone marrow, called the stem cell niche. There, besides several cell types like mesenchymal stem/stromal cells (MSCs), osteoblasts and osteoclasts, soluble factors and molecules of the extracellular matrix (ECM) play important roles in regulating HSC behavior. For biomimicking this niche, exact positioning of the different cell types with regard to each other in a bone marrow ECM-mimetic matrix is necessary. The glycosaminoglycan hyaluronic acid (HA) is a molecule of the bone marrow ECM and is known to influence hematopoiesis as well as MSCs. We chemically modified HA to design a polymer that forms a 3D-printable hydrogel, thereby benefitting from the biological qualities of HA and from the possibility to chemically tune the properties of the HA-bioink. MSCs and hematopoietic cells could either be included in the hydrogel during the printing process or be injected into the gel in a second step, which was allowed by the self-healing properties of the gel. In a last step, covalent crosslinking stabilized the printed construct to ensure integrity during cell culture. The beneficial printing properties of our HA-hydrogel allow exact positioning of cells and thereby enable designing an HSC niche model as needed to study cell-cell or cell-matrix interactions in a healthy or diseased system.