Hermatypic corals exhibt ecological patterns which have been called community structures. Of those, the patterns appeared in zonation, distribution of diversity or coverage and the ecological succession are discussed. Studies on the ecological structures in the Indo-Pacific (in-cluding the Ryukyu Islands) and Atlantic coral reefs are reviewed in order to find out the general community structures. Quantitative models on the origin of the structure are also introduced in some cases. Especially, a dynamical model is proposed for the ecological sucession on the basis of the dynamics of species diversity.