Abstract : In insects, chitinases are key enzymes in chitin degradation, and especially during molting and growth process. As a consequence, chitinase metabolism in an interesting targets to develop new alternatives method to manage insect pests. In this project, we evaluated the relevance of the disturbance of aphid chitinase activities. The impact of chitinases was evaluated on M. persicae development via in planta tests, rearing aphids on potato plants expressing an insect chitinase (Phaedon cochleariae, Coleoptera) and via in vitro tests, via an artificial diet containing a bacterial chitinase (Serratia marcescens). Probiotic effects were described in both cases and our results, question us on the reliability of the use of chitinases as biopesticides to fight aphids. We evaluated the effects of an antagonist strategy based on chitinase inhibitors. Four of them, from different origins were tested via an artificial diet. Our results reported for the first time the inhibitory activity of chitinase inhibitors on aphids. We focused our searches in this way with the aim to identify new chitinases inhibitors. In a first approach, we initiated the purification of M. persicae chitinases and in a second one, we evaluated the effects of oligossacharides which mimic chitin and chitinase inhibitors. Our results highlight the potential use of chitinase inhibitors as new bioinsecticides in pest management programs.