This research developed a new material made from leftover mushroom compost mixed with iron to clean water polluted with nitrate, a common problem in farming areas. The material works by attracting and trapping nitrate particles, and when tested, it successfully removed up to 19.88 mg of nitrate per gram of the material used. The best results occurred at neutral pH levels and after two hours of contact time. This affordable, environmentally friendly solution could help communities improve their water quality without expensive chemical treatments.