The reinforced polymer composites from recycled plastic are polymer blends made from recycled polymers that are reinforced with glass fibers and mica. In particular, the reinforced polymer composites are blends of recycled low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene (PP) with a mica filler that are reinforced with glass fibers, where the low-density polyethylene forms between 30 wt % and 35 wt % of the composite, the high-density polyethylene forms between 15 wt % and 17.5 wt % of the composite, the polypropylene forms between 15 wt % and 17.5 wt % of the composite, the glass fibers form between 15 wt % and 40 wt % of the composite, and the mica forms up to 15 wt % of the structural element. The resultant reinforced polymer composite has a relatively high heat deflection temperature, good mechanical properties (such as increased stiffness and strength), improved thermal stability, and is cost effective to manufacture.