Abstract: Using polyolefin resin as the matrix and metal hydroxides magnesium hydroxide and aluminum hydroxide as flame retardants, low smoke halogen-free flame retardant polyolefin composite materials were prepared by compounding granulation process. The effects of resin, flame retardant, silicate flame retardant synergist, and phosphorus nitrogen flame retardant on the peak heat release rate(PHRR) and total heat release(THR) of low smoke halogen-free flame retardant polyolefin composite materials were studied. The results showed that the influence resins on PHRR and THR was ranked in descending order as polyolefin elastomer(POE), linear low-density polyethylene(LLDPE), and ethylene vinyl acetate copolymer(EVA). Therefore, the use of POE should be minimized in low heat release materials; The combination of magnesium hydroxide and aluminum hydroxide has lower PHRR and THR than using aluminum hydroxide or magnesium hydroxide alone. When the ratio of magnesium hydroxide to aluminum hydroxide was 1:5, the heat release of the material was the smallest; Although silicate flame retardant synergists have good carbon layer integrity after combustion, they released a large amount of heat after combustion, which may be due to the different types of organic modifiers used or the high content of organic modifiers, making the material easier to ignite in the early stages of combustion; Phosphorus nitrogen flame retardants could be used in combination with aluminum hydroxide to not only reduce the heat release of the material, but also further enhance the strength of the carbon layer, while the combination of phosphorus flame retardants with magnesium hydroxide could actually cause a decrease in the flame retardancy of the material.