The geometries and energetic, electronic, and magnetic features of transition metal-doped germanium (TMGen with TM = Ru, Rh; n = 1-20) clusters are systematically studied by means of first principle computations on the basis of the density functional theory (DFT) approach. The doping TM atom largely participates to strengthen the Gen cluster stability by increasing the binding energies. A good stability is obtained for RuGe12, RhGe12, and RhGe14 clusters. The various explored isomers of TMGen clusters possess a total spin magnetic moment going from 0 to 2μB, except for RhGe2 with 3μB. These results open nice perspectives of these good candidate clusters for applications in nanoelectronics and nanotechnologies.