The production and consumption of mushrooms of the genus Pleurotus in the present day has grown due to the fact they are a source of nutrients, are developed in a short time, and because of the diversity of substrates used in cultivation. The objective of the following work is to determine the best alternative of substrate for the cultivation of the mushroom Pleurotus ostreatus in agroindustrial waste of the sierra and the Ecuadorian Amazon (barley straw, wheat straw, bean peel, sugar cane bagasse, maize waste) in an individual form. An experimental design of a factor was used and variables were evaluated statistically such as the yield, the biological efficiency, precocity and the growth speed. The results statistically obtained indicate the barley straw as the best treatment, with a performance of 21.08%, biological efficiency of 84.83%, precocity of 18.6 days, growth speed of 5 days, pileus diameter of 4.9-5.9 cm, and protein content of 3.08%.