[en] Crystal structure of UCo₅Si₃ has been determined: a=14.85 A; c=3.701 A; spatial group P6₃/m; Z=6. All atoms occupy regular systems of the points 6(h) xy 1/4, R=0.105 for 380 reflections. The structure of UCo₅Si₃ belongs to the series containing the structural types of ZrAlNi(Fe₂P), Zr₂Fe₁₂P₇, Hf₂Co₄P₃, UNi₅Si₃ with a general formula of Mn₂+5nN(N₂+5n)/2, where M is the metal component, and N is the non-metal component. The UCo₅Si₃ structure is the member of this series with n=4. ZrCo₅Si₃ is isostructural to UCo₅Si₃: a=14.72 A; c=3.624 A