Hydrogel fibers are structurally and biologically useful devices for differentiation of stem cells and fabrication of filament-like tissues. We established cell-laden degradable hydrogel fibers through visible light-initiated crosslinking to differentiate stem cells and fabricate filament-like tissue. Human adipose stem cell (hADSC)-laden fibers were fabricated by cross-linking phenolic-substituted alginate and gelatin (Alg-Ph and Gela-Ph respectively) in an aqueous solution containing cells. The crosslinking of phenolic moieties was mediated by ruthenium(II) tris-bipyridyl dication (Ru(II) bpy and sodium ammonium persulfate (SPS) and irradiating visible light. The hydrogel microfiber fabricated with desirable geometries and dimensions. The encapsulated hADSCs proliferated and grew within hydrogel microfiber, maintained their multipotency ability and formed filament-like constructs. The filament-like tissues covered with an additional heterogeneous cell layer was made by degrading the fiber membrane using alginate-lyase after covering the fiber surface with vascular endothelial cells. Cellular viability is preserved during Alg-Ph and Gela-Ph hydrogel fiber fabrication and filament-like tissue formation. These results demonstrate the feasibility of Alg-based hydrogel fibers obtained through the Ru/SPS-mediated crosslinking system and visible light irradiation for the engineering of filament-like tissues and cell-based therapeutic treatments.