Miocene carbonate reservoirs may contain appreciable amount of microporosity in grain, cement or matrix. Depending on the crystallometry and morphometry of micrite particles, microporosity can vary both in amount and in nature. Different kinds of micrite microtextures may produce different types of microporosity. This study proposes a classification of micrite microtextures and microporosity. Four different types of micrite microtextures are classified in this study; these are rounded micrites, subrounded micrites, microrhombic and polyhedral micrites, and compact anhedral micrites. Four different types of micropores are classified based on their pore sizes. These are very fine, fine, medium, and coarse micropores. The classification of microporosity allows its occurrence in carbonate reservoirs to be explained depending on micrite microtextures. The classification of micropores in terms of their micrite microtextural occurrence lead us to define the micropores that are contributing to the permeability of the reservoirs and allow fluid flow in carbonates. The classes of micropores together with the corresponding micrite microtextures of their occurrences help to define the potential reservoir rocks in terms of micrite microtextures. © Copyright 2011, International Petroleum Technology Conference