The modified nano aluminum magnesium hydrotalcite is an excellent environmentally-friendly flame retardant, with high efficiency, non-toxicity, low smoke production, and a high cost-performance ratio. Hydrotalcite has a structure and composition similar to magnesium hydroxide and aluminum hydroxide. When heated, it decomposes and releases large amounts of water and carbon dioxide while absorbing a significant amount of heat, thereby reducing the temperature of the combustion system. The water vapor and carbon dioxide gas released during decomposition can dilute and block flammable gases. The magnesium and aluminum oxides formed from thermal decomposition react with the charred materials produced when polymers burn.