The average production of one trawl boat operating off the coast of Sinai was calculated, during fishing season 2021 were 34.9 tons. The negative impact of the trawl net on the Mediterranean catch on the Sinai coast was studied by taking monthly samples of 20 kg of each type during 2021. Fish were divided into small fish and mature fish according to length at first maturity recorded by the previous studies of these species in the same area or adjacent areas. The results showed that the percentage of small fish 47.4% of the production of the trawl net. The negative impact on the biomass from juvenile and discards (ELafsha) were 3.16; 5.04; 6.25; 9.21; 1.41; 4.51; 9.13; 5.84; 1.37; 0.59; 2.52; 7.35; 6.39; 1.23; 0.26 and 3.73 ton (total 68 tons) and losses income were 0.789; 0.605; 1.563; 2.302; 0.311; 0.451; 0.467; 0.356; 0.913; 0.147; 0.328; 2.557; 0.098; 0.037; and 0.521 (total 12.04 million L.E.) from shrimp; Crabs; Cattle fish; Squids; Bogue; Med. Horse ; Common Sole; Atlantic Lizard Fish; Red mullet; Grey gurnard; Common pandora; Grouper; Gobius niger; European eel and Merluccius respectively for one trawl net during fishing season 2021 in the Mediterranean coast Sinai.