The Pt/Rh(110) bimetallic surface was prepared by electrochemical deposition of Pt ions on a Rh(110) surface. The Pt/Rh(110) surface was stable at 760 K in vacuum, but Ph atoms were extracted onto the Pt layer at 760 K by heating in O-2. The LEED pattern sequentially changed from p(1x1) with high background to a p(1x3) and a c(2x2) by heating in O-2. When the c(2x2) surface was heated at 760 K in H-2, the LEED pattern changed to p(1xn). Extraction of the Ph atom occurred also during the NO + H-2 reaction, which was monitored by cyclic voltammograms. The p(1xn) Pt/Rh(110) surface is highly active for the NO + H-2 reaction, which suggests that the extraction of Ph atoms onto Pt layer is responsible for the activation of the surface for the NO + H-2 reaction.