The invention discloses a foam material for tables and chairs for children playing and a preparation method. The foam material is prepared from the following ingredients calculated by weight: 40-60Phr of a modified polystyrene foam material, 10-20Phr of regenerated low-density high-pressure polyethylene, 0.2-1Phr of a foaming agent, 0.5-2Phr of zinc oxide, 1.0-3.0Phr of stearic acid, 0.5-1Phr of a peroxide crosslinking agent, 0.02-0.1Phr of a crosslinking adjuvant and 15-20Phr of heavy calcium carbonate; the foam material for the tables and the chairs for children playing is prepared through such technological processes as material mixing, open milling, sheet delivery, vulcanizing and foaming, cooling and molding, and processing, by modification, the melting point of polystyrene drops to 130 DEG C, and molding foaming can be carried out. The foam material disclosed by the invention not only has the advantages of a common foam material, but also has excellent impact resistance, compression resistance and relatively strong rigidity and hardness, the safety performance of the tables and chairs for children playing is improved, the service life of the tables and chairs for children playing is prolonged, and compared with a raw wood material, the cost is greatly reduced.