The study conducted during (2017-2018 and 2018-2019) at Plant Protection Farm, Faculty of Agriculture, Assuit University, Assuit, Egypt on tomato variety 765 planted on the 10^th of September for each season in an approximate area (315 m²) in order to compare the efficiency of three Neonicotinoids [Thiamethoxam (Actara 25% WG), Imidacloprid (Best 25% WP ), Acetamiprid (Mospildate 20% SP)] in Nano and commercial formulation size using recommended dose for them and the half-recommended dose for nano-insecticides against tomato leaf miner, Liriomyza trifolii Burgess (Diptera: Agromyzidae). The randomized complete block design (RCBD) was applied with three replicates/ treatment and three control in a total of 21 plots. The replicate (plot) size was 3 ×3.5 m and consists of three rows planted with 5 plants/ row.
            The nano and commercial insecticide sizes showed highly significant results in reducing the infestations of mines in tomato during the studied seasons in the first and second week after (1^st and 2^nd) spray compared with control. The nano-thiamethoxam 1x was the best for mines reduction followed by nano–acetamiprid, and nano-imidacloprid. However, there were no significant differences between commercial and nano-formulations in mines reduction % and the highest reductions showed by nano treatments. However, the treated tomato by the half-recommended rate of nano and commercial formulations showed the same reduction results.