Catalyst characterization and activity of Zr or Mn containing Ru/Q10 were investigated for Fischer-Tropsch synthesis in a stirred slurry tank reactor. The addition of Zr or Mn in Ru/Q10 enhanced CO conversion, C5+ selectivity and space time yield at 503 K, 5.0 MPa and 1800 h(-1), and the catalyst activity was highly stable during the reaction. The addition of Zr or Mn can inhibit the oxidation of Ru species and it can maintain the active reduced Ru atoms on the catalyst surface. Ru/Q10 showed lower activity compared to Zr or Mn containing catalysts and it was deactivated due to the oxidation of active and reduced Ru species. Catalyst characterization results of BET, BJH, XRD, TPR, H-2 chemisorption, TEM, EDS and XPS were studied, and it suggests that a small amount of Zr or Mn addition can increase the surface atomic concentration of Ru due to the inhibition of the oxidation of the Ru species. ZrO2 in Ru/Zr/Q10 and MnO in Ru/Mn/Q10 were formed on the catalyst surface, and it can be related to the maintenance of the Ru species in a reduced state, resulting to enhanced catalyst activity and stability. (C) 2015 Elsevier B.V. All rights reserved.