The heterobimetallic N-heterocyclic dicarbene (NHDC) rhodium ruthenium complex [Ru(OAc)(Mes-NHC-methyl-PPh2)(Mes-aNHC-methyl-PPh2)RhCl(cod)] (4) is obtained from a mixed normal/abnormal bis-NHC ruthenium complex via transmetallation by addition of [RhCl(cod)]2 in THF at 40 °C, applying Ag2O as base. Crystallization is achieved by layering a solution of 4 in THF with Et2O. The complex is applicable as a catalyst in the transfer hydrogenation (TH) reaction of acetophenone, exhibiting a turnover frequency (TOF) of 6 700 h−1 with 80% conversion after 25 min (0.10 mol% catalyst, iPrOH, 80 °C, 2.00 mol% NaiOPr). These results are compared to an analogous iridium ruthenium NHDC complex.