The biology, ethology, and impact on saltcedar ofConiatus tamarisci(F.) (Coleoptera: Curculionidae, Hyperini) were studied in southern France, in nature and in a field laboratory, at each developmental stage. Adults and larvae fed on saltcedar buds, leaves, and stems during the entire vegetative phase of the host plant. The adults began ovipositing 4–5 days after emergence and laid an average of 100–200 eggs per female. Development from egg to adult required less than 1 month during the summer. Adults lived 8–10 months and mortality was low. In the area studied, three or four generations developed per year depending on climatic conditions. The adults overwintered and survived periods with temperatures below 0°C. This weevil is a promising candidate for biological control of saltcedar in North America.