Water vapor permeability (WVP) is an important parameter for systems used in edible coatings of food. WVP should be optimized to a minimum value to control the passage of fluids between food and its environment. In this work, Box-Behnken design was applied to optimize the edible coating based on alginate, soluble starch and microcrystalline cellulose (MCC) to its minimum. The optimized theoretical value of WVP was 9.94 g mm/m2 day kPa which was in a greement with the experimental obtained value. The molecular structure of the prepared edible coating films was verified using FTIR. MCC addition significantly improved the thermal and mechanical properties of the edible coating. Shelf-life studies on green capsicums coated with the optimized edible system showed great resistance to mass loss and spoilage. The prepared edible coating, based on the excellent obtained data, could be used potentially to extend the shelf-life of food.