Neem Azal T/S (commercial formulation of Neem seed kernel extract) was tested for its efficacy as a deterrent, toxicant or growth inhibitor against the two spotted spider mite, Tetranychus urticae Koch. Addition of T/S Fort increased its effect on mite females and eggs. Neem Azal T/S with T/S Fort at the ratio of 1:2 showed the highest acaricidal activity compared with the other formulations tested. Newly emerged females sprayed with the median concentration (0.086%) of Neem Azal T/S induced a serious chronic effect on their biotic potential. A high significant reduction in the egg production with an increase in percent of female sterility and a significant decrease in longevity were recorded. However, egg hatchability was slightly reduced while durations of immature stages were significantly increased.