In order to assay the triatomine infestation and domiciliation in the ruralIn the state of Ceará, the presence of triatomines has been known for a long time, as Alencar (1987) has shown in a research that compiled former surveys carried throughout the state. Alencar et al. (1976) have demonstrated that vectors have not been found in only 9 out of the 141 municipal districts that comprise the geographic division of the whole state of Ceará. The authors have cited the semi-domestic Triatoma brasiliensis as being a primary transmitting species and with larger distribution in that state, found in 91.5% houses of municipal districts, many times with high Trypanosoma cruzi infection indexes. Triatoma pseudomaculata, which is believed less domestic, was found in 68.8% of the municipal districts, with an average infection index of 4.2%. In the distribution ranking, the third species in Ceará was Panstrongylus megistus, displaying a variable infection index; this species was found in 61.7% of the municipal districts. Rhodnius nasutus, with an average of 1% infection index, was found in 17.7% of the municipal districts; Panstrongylus lutzi was found in 18.4% of the municipal districts, presenting an average of 17.9% of infection indexes (Alencar et al. 1976).The objective of the present work was to determine infestation indexes, colonization, and density of triatomines in domiciliary units (DUs) that include intradomicile, peridomicile, and ecotopes found in wild habitats of the four localities that belong to the rural area of Jaguaruana municipality, Ceará, Brazil, formerly considered to be highly infested by these vectors. The indexes were determined by relating them with variables such as type of house's wall type and number of peridomiciliary annexes. The authors have also determined the indexes of natural T. cruzi infection in triatomines captured in each studied habitat and ecotopes.