Classical and artificial xenodiagnostic techniques made with Dipetalogaster maximus of first stage were performed simultaneously in 57 patients with chronic T. cruzi infection (22 male and 35 female patients, aged 7-80 years). With the exception of two patients with megaoesophagus, all had two previous positive serological reaction and a further test was done at the time of the examination. The patients came from the outpatient department of the university hospital or were resident in Mambaí, Goiás. Of the 57 patients, 24 (42%) had a positive xenodiagnoses. Of a total of 114 tests performed, 36(32%) were positive. Comparing the two xenodiagnostic techniques, no significant advantage was apparent statistically (p = 0.42), but the artificial technique has advantages because the blood is offered for triatomines through a device while in the classical technique, the triatomines suck through the patient's skin.