Cooking oil is an indispensable ingredient in everyday family cooking. The oil after use is often discharged directly into wastewater systems, leading to risks of environmental pollution, water pollution, clogging of drainage systems... In recent years, water hyacinth plants have been considered weeds, floating on rivers, canals, ponds and lakes, obstructing the circulation of boats and preventing water flow. Water hyacinth plants are often found in large rivers and almost no one cares about their uses, making them truly wasteful. Realizing the flexibility of water hyacinth when dried, it can be woven into pieces with good absorbent properties, our team has researched using water hyacinth as a material to absorb used cooking oil that is discarded into the environment. school. The research uses the main methods of experimental method and sample analysis method in its research. The result is that a product that absorbs discarded cooking oil scum is formed and is tested for cooking oil contaminated water with results consistent with QCVN 14:2008/BTNMT. The purpose of the research is to find effective products to absorb discarded cooking oil to save costs and contribute to environmental protection. The problem of using naturally available materials to create products that absorb cooking oil scum at the same time solves two current environmental problems. The research is a preliminary result, so there are still many shortcomings. We hope that in the future there will be further research to make the product more and more perfect