The adsorption of oxygen on Rh(311) has been investigated by means of He scattering. The formation of ordered (2 × 1) and (1 × 3) structures was observed. (The notation refers to the centered rectangular unit cell of the substrate.) Ordered oxygen structures could only be prepared by annealing oxygen pre-exposed surfaces to at least 450 K. Both oxygen structures are stable up to 900 K. For the (2 × 1) phase evidence is presented that suggests that the oxygen atoms are adsorbed along every second close-packed row. Oxygen removal from the (1 × 3) phase by hydrogen at 430 K leads to a c(1 × 3) structure, which is metastable and reverts to the clean c(1 × 1) surface above 500 K. The presence of a pronounced rainbow pattern for the c(1 × 3) signals unambiguously that its structure is of the missing-row type. This suggests that oxygen induces a surface reconstruction in the (1 × 3) phase, whereby at least one out of three close-packed rows is missing and the oxygen atoms fill the resulting deep troughs.