The most significant aspects of the life cycle of Promecops claviger Hustache (Coleóptera: Curculionidae) that could be used for the management of this pest, are treated here. Weekly samples were taken insoybean fields during 1993/94 and 1994/95 growing seasons in order to assess adult populations. Soilsamples were also taken for larvae and pupae. The adults feed on seedlings since soybean emergence. Highpopulations sometimes occur during the vegetative stage. Larvae feed on nodules affecting them up to 1%.Plants are not damaged when environmental conditions are favorable for their development