The lesser date moth, Batrachedra amydraula Merck is one of the most important pests affect date palm fruits, which cause great losses to the yield, whether in quantity or quality. This study was conducted in Basra province / Al-Qurna district to study the effect of harmal plant seeds on the numerical density, percentage and severity of infection caused by lesser date moth on the date palm trees. The results showed that the highest number of lesser date moths’ population density was appeared in the fogging treatment (111.3 / trap), while the lowest was in the fumigation treatment (64.3 / trap). The lowest percentage of infection by lesser date moth was in the aqueous extract treatment of (29.7%), while the highest was in the fumigation treatment (31.4%). In the first period, the treatment of aqueous extract gave the best results, as the percentage of infection was (17.8%). The lowest rate of infection severity was also in the treatment of aqueous extract (2.2 / 5 fruit), while the highest was in the fogging treatment (6.5 / 5 fruit). In the third period, both treatments of fumigation and fogging gave the best results, as the infection severity was (0/5 fruit) compared to the control for the same period of (8.9 / 5 fruit). The treatment of aqueous extract gave the best results in reducing the severity of infection by lesser date moth, while the treatment of fogging gave the best results in reducing the number density of lesser date moth.