Field experiments were carried out during the two summer seasons of 2016 and 2017 at The Experimental Farm, Faculty of Environmental Agricultural Sciences, Arish University, North Sinai, Egypt to study the effect of mulch (without mulch and straw mulch) on two colored sweet pepper hybrids (“Yellow Star F1" and “Red Star F1", Capsicum annuum L.). Transplanting was carried out on 19^thMay. Straw mulch was added after 10 days later. The experimental plot area was 15m² (15 m long and 1.0 m wide). Drip irrigation system was used. Each experimental plot had one dripper line, the distance between plants in the same row was 50 cm, which gave, planting density of 2.0 plants m^-2. Split -plot design with three replicates was used, where sweet pepper hybrids were randomly arranged in the main plots, and mulch treatments were randomly arranged in the sub plots. ‘Red Star F1' hybrid recorded the highest values of plant height, number of leaves and leaf area as well as plant fresh and dry weight traits at 75 days after transplanting in both seasons. Red Star F1'and Yellow Star F1' both with mulch recorded the highest values of all vegetative growth traits and marketable yield traits in both seasons. Mulch treatment had higher values of all studied marketable yield traits (number of fruits/plant, mean fruit weight (g), and yield/plant (kg) in both seasons. Using straw mulch increased number of fruits/plant by 48.59% as compared to without mulch treatment. The highest values of all marketable yield traits in both seasons were recorded with ‘Red Star F1' or ‘Yellow Star F1' both with mulch.