SDS-PAGE profiles of both sexes of the haemolymphs of Panstrongylus geniculatus from different Venezuelan regions (savannas, piedmont, tropical forest and urban areas) were compared. It was determined that the haemolymphs showed a different electrophoretic profile, with proteins that ranged from 14 to 164 kDa. The most representative protein band in the profile of females was observed in two sectors: between 164 and 46 kDa and between 33 and 30 kDa. The main illustrative protein band in males was observed in one region: from 46 to 35 kDa. The Haemolymph composition of P. geniculatus from populations evaluated in this work expressed high homogeneity of this species with a clear difference between males and females. This similarity may be useful for control of these insects, taking into account that the genetic stability may be very important, since the use of an insecticide in a population with these characteristics is always more successful. According to the bibliographic review, this is the first study of haemolymph from Panstrongylus geniculatus.