Abstarct: Abstract From the past so far, many researchers have studied the mechanical behavior of different soils with low strength capacities. They have tried to reinforce them in different ways, to ultimately utilize them as a reliable building materials. One of the methods for soil stabilization or reinforcement, is to use Polyethylene terephthalate (PET) plates and Fly ash (FA), Which they are part of the industrial and urban waste respectively. Due to the increasing production of industrial by-products and urban plastic wastes, concerns of global communities are the lack of landfills, high cost of recycling, or producing contaminants caused by burning these wastes. Use of PET plates that have a similar performance to geogrids, along with FA, can be a good technique to eliminate the risk of unnecessary production of solid wastes and help to protect the environment. In this study, it has been evaluated the mechanical behavior of Anzali port sand, reinforced with PET netted plates and stabilized by FA, in addition to 3% weight of sodium hydroxide. PET netted plates are located in different laxyers of soil stabilized by FA and unconfined compression test (UCS) are performed on the specimen with optimum moisture content. The results of UCS test show that the axial resistance value of reinforced soil with three laxyers of Geopet and 15% of FA increases by 15% and 49 % respectively, compared to specimen including 10% and 5% of FA.