Polyethylene terephthalate (PET), a strong, stiff synthetic molecule that belongs to the polyester family of polymers. Despite its many advantages, it has a number of disadvantages as it is widely employed in the production of a wide range of items (e.g., beverage bottles), therefore large-scale recycling has become a serious environmental problem. Herein, we developed MIL-125 (a Ti based metal-organic framework (MOF)) by linking Ti metal salts into the linker terephthalic acid (TPA) which was extracted from the PET bottle waste. Briefly, at first, we extracted TPA linker from waste PET bottles via alkaline hydrolysis, then MIL-125 was developed via simple hydrothermal technique using TPA and titanium isopropoxide. The successful preparation of as obtained MIL-125 was further confirmed via XRD, Raman, FTIR spectra and FESEM characterizations. Furthermore, the as-obtained MIL-125 was employed as an electrode material and electrochemically tested in 1M H₂SO₄ electrolyte in three-electrode configuration. MIL-125 material rendered high specific capacitance of 127 F/g at a current density of 0.5 A/g along with a long cycle life of 90.5% over 5000 charge-discharge cycles. Our research proves that MIL-125 derived from plastic waste has therefore been proven to be a viable electrode material, which hold tremendous promise for practical supercapacitor applications.