Abundance, diversity and temporal dynamics of two chalcidids (Hymenoptera, Chalcidoidea, Chalcididae) taxocoenosis from two natural habitats from the Comunity of Madrid (Central Spain) the biogeological station of El Ventorrillo (Sierra de Guadarrama) and the Monte de El Pardo are studied. All the material was collected by means of Malaise traps, between 1988 and 1992. Traps were kept working during at least one all year on both localities. Eighteen species have been identified from El Ventorrillo and twenty from El Pardo. The total number of species was twenty-four. It represents about 42% of the species formerly known from the Iberian Peninsula and 33% of the European ones. Specially important is the presence of non-described species belonging to the genera Belaspidia Masi, Antrocephalus Kirby and Hockeria Walker. Moreover, one species from the genus Tanycoryphus, which have recently been described (T. ibericus Rasplus & Delvare), represents the first citation of the genus in Europe. The genera Antrocephalus Kirby and Haltichella Spinola and the species: Euchalcis unicolor (Lucas), Hockeria magna (Boucek), Haltichella rufipes (Olivier), Psilochalcis subarmata (Förster) and Proconura punica Masi are reported for the first time in the Iberian Peninsula. Some parameters related to structure and temporal dynamics of both localities are discussed. El Pardo shows a greater abundance and species-richness, while diversity, uniformity as well as dominance are similar in both localities. The dominant species from the taxocoenosis of El Ventorrillo are: Hockeria unicolor y Hockeria bifasciata and in El Pardo: Proconura nigripes y Hockeria unicolor. Annual temporal dynamics displays abundance and richness peaks in July-August on both studied areas.