Two-field experiments were carried out during two-successive summer-seasons (2015-2016) at Vegetables-Research-Farm, Kaha-Qalubia-Governorate, Egypt. Study aim to investigate three-dates effect of sowing (1^st-April, ^mid-April and 1^st-May) and two-mineral nitrogen recommended doses 100 and 50% under field of Etiella zenckenella controlled by (Trichogramma),and their interactions on growthing, nutrient concentration, yield and components of cowpea-plants (Vigna unguiculata L.). Obtained results showed, first sowing-date was desirable significant effect on growth, yield and components i.e. seed number/pod, weight 100-seeds and seed yield/feddan in both seasons. Also, 1^st-sowing-date×60kg/fed N-dose with Trichogramma releasing recorded, highest vegetative growth characteristics, yield traits, highest nitrogen concentration, phosphorus, potassium and protein-content in seeds. Also, full nitrogen dose (60kg/Fedd.) along with Trichogramma utilization at all sowing-dates gave best growth parameters and seed yield. Infested%/pods decreased after Trichogramma treatments with about 54.1, 42.4 and 39% in 1^st-season and 82.3, 82 and 78.5%, in 2^nd, at 1-April, Mid-April and 1-May, when compared with control. However, significant differences in infested%/pods were observed between three planting-dates. Moreover, infestation% increased by delaying planting-date in both seasons. No significant differences were found in percent reduction of % infested pods between 1^st and 2^nd planting-dates of cowpea treated with Trichogramma. Itcould be recommended release of egg parasitoid T. evanescens combined with select 1-April planting-date against E. zinckenella.