The invention discloses a polypropylene-containing flame retardant wood and plastic composite board and a production method thereof. The composite board comprises, by weight, 100 parts of PP resin, 20-40 parts of PLA resin, 100-200 parts of wood powder, 5-15 parts of seashell powder, 20-40 parts of nanometer calcium carbonate, 5-10 parts of aramid fibers, 5-10 parts of sepiolite fibers, 1-3 partsof a maleic acid grafted PE wax compatibilizer, 1-3 parts of a plasticizer, 0.5-2 parts of a flame retardant, 1-3 parts of a stabilizer, 1-3 parts of methyl allyl polyethenoxy ether, 0.5-2 parts of octaphenyl silsesquioxane, 1-3 parts of phytic acid and 1-2 parts of acrylic acid rosin polyoxyethylene sucrose ester. All above components have good coordination effects and good compatibility, so theproduced polypropylene-containing wood and plastic composite board has the advantages of high strength, strong impact resistance, good resistance to wear, weather and heat, non-deformation, good stability, good flame retardancy and good antibacterial effect.