Veranda nets are major technique in Bardawill lagoon, may be due to its ability to target different fish species and less effort required in operating it despite the majority of catching them in this study were non targeted (small size and immature). To manage marine fisheries effectively, we must assess and manage by catch. Data were collected monthly from three specified fishing vessels of Veranda nets of (Mugil cephalus) it operated in Bardawill lagoon for each fishing unit from May to November 2018-2019. Average catch of Flathead Grey Mullet (Mugil cephalus) from juvenile and adult was 513.6 kg (24.7% of total catch by veranda nets) and 620.3 kg (29.8% of total catch by veranda nets) in spring; 838.5 kg (19% of total catch by veranda nets) and 1363.8 kg (31% of total catch by veranda nets) in summer and 400.5kg (15.2% of total catch by veranda nets) and 832.3 kg (31.5% of total catch by veranda nets) in autumn, respectively. Our results indicated that, the landing of Flathead Grey Mullet juvenile leads to more losses of stock biomass which formed 76835.1 12544.3 and 59919.4 Kg for spring, summer and autumn, respectively and the ≈ 10.5 million LE losses in one fishing season 2018 and 2019.