Nerium oleander (Apocynaceae) is evergreen shrubs widely used for ornamental purpose in mediterranean region. The present investigation, revealed for the first time the insecticidal effect of ethanolic extract from leaves of this plant against 2nd instar larvae of the medically important false stable fly Muscina stabulans (Diptera: Muscidae). LC50 of the extract was 113.66 ppm. This dose delayed larval and pupal duration suppressed oviposition and decreased adult longevity of the survivors. Morphogenic abnormalities were recorded and photographed in larval, pupal and adult stages, which were produced from treating 2nd instar larvae with different concentrations of the extract.