Plant communities of the arid deserts are facing several stresses, such as high temperatures, repeated draught and overgrazing. The impacts of protection from grazing for two years on plant diversity, richness, abundance and community structure were assessed in sand dunes and gravel plains of Dubai Desert Conservation Reserve. During the two years, the study area received significantly less rainfall than the average and consequently was a good chance to assess the impact of draught and protection from grazing on community attributes of the two substrate types. Protection for two years significantly increased plant diversity, abundance and sizes in sand dunes. In gravel plains, however, protection resulted in the reduction of most of the community attributes.