Abstract: In 1990-1991,two breeding sites of the Relict Gull (Larus relictus) were discovered successively on Ordos Highland of Inner Mongolia with a total of 1115 nests of colonies occuring in 1991 making it the largest breeding population of the gull in the world.By the field work results as well as previous reports on the gull,I.e.,breeding in desert lakes and only nesting on islets as known so far of the breeding site selection,it might be concluded that this gull species is of high adaptability to the desert habitat and therefore might be properly regarded as one of the representatives of those desert birds.It is also observed that on ordos Highland the Relict Gull and the Gull-billed Tern (Gelochelidon nilotica) are the companion species with each other,though in most cases the Relict Gull is dominant,competition and interdependence existing between the two species.The wetland birds community occuring at the breeding sites of the Relict Gull also shows a strong tendency of being a more affinity of the specific desert bird group.