Abstract: A geogrid prepared by recycling medical waste and a preparation method therefor, and use in foundation reinforcement. The method includes: recycling medical waste for treatment and processing the medical waste into a crushed material; adding modified filler and processing aids, and selecting high-strength fiber bundles for compounding and melting with the crushed material and pressing and stretching to prepare a geogrid. The medical waste is any combination of one or more used medical plastic products and medical plastic products that expire and are not used. The high-strength fiber bundles are more than one bundle of fiber materials commonly used for manufacturing geogrids on the market. The modified filler is a stabilizer for improving the stability of component materials to heat and light. The processing aids are enhancers for improving the performance of the component materials.