The crystal structure of U 3 Ga 2 Ge 3 has been investigated by means of neutron powder diffractometry in the range from 1.5 to 100 K. Full matrix full profile refinements of the nuclear structure at 100 K revealed a new structure type with almost fully ordered distribution of Ga and Ge atoms in the 8csites of space groupI4. The new U 3 Ga 2 Ge 3 type is a low symmetry derivative of the ordered antitype-Cr 5 B 3 (I4/mcm),R I =0.032,R F =0.030. From model refinements, eventual interstitial nonmetal occupation in the metal octahedra U 1 Ge 1 Ge 2 Ga 2 or U 2 Ge 2 Ga 2 or in metal tetrahedra Ge 2 Ga 2 is ruled out. At temperatures lower thanT c =90 K uranium atoms order ferromagnetically as monitored by the intensity of the magnetic reflection M I (011) . Due to the observation of the M (011) reflection, the magnetic spin structure is consistent with the symmetry of the noncentrosymmetric space groupI422. The lower symmetry invokes a splitting of the 4asites of the parent Cr 5 B 3 type (I4/mcm) into two twofold uranium sites 2aand 2bofI422. Besides the uranium atoms in 8j(μ U =2.57μ B ), only the uranium atoms in 2awere found to carry a magnetic momentμ U =2.45μ B . All moments are parallel to the crystallographicaaxis. To comply with the symmetry of the Ge/Ga atoms, magnetic and nuclear structure have to be described in space groupI4. The reliability values for the 1.5 K diffractogram were:R I =0.024,R F =0.019, andR mag =0.033.