To explore the contribution of agricultural practices on enzymatic activity in Anopheles gambiae populations, collections of Anopheles gambiaelarve were done in cotton vegetable farming (famers use for both,insecticides for pest control) and in subsistence farming (no insecticide) from the district of Banikoara, located in Benin. Enzymatic activities such as total protein, monooxygenase P450, Glutathione-S-Transferase and esterasewere investigated on F1 generation females aged 3-5 days. Results from this study showed a significant high level of Glutathione-S-Transferase and monooxygenase P450 activities from the wild populations of An. gambiae particularly in cotton and vegetable farming areas compared to the susceptible Kisumu strain (control) (P<0.05). However, there is no significant difference in the level of Esterase (α and β-Naphthyl) activity from the 3 wild populations compared to the control (P>0.05). These findings confirmed the contribution of agricultural practices on theemergence of enzymatic activity in Anopheles gambiaes.l particularly on Glutathione-S-Transferase, and monooxygenase P450. However, the same level of the wild populations activity in esterase compared to the control could be explained by the involving of many insecticide resistance mechanisms of An. gambiae associated to the level of enzymatic activity in An. gambiae populations in this locality.