The invention discloses an environment-friendly inflaming-retarding foam material and a preparing method thereof and relates to the technical field of foam material preparation. The material is mainly prepared from polyethylene, phenol-formaldehyde resin, melamine polyphosphoester, graphene, ammonium bicarbonate, tephra, diisopropyl azodicarboxylate, neopentyl glycol, zinc oxalate, ammonium fluoroborate, basic magnesium carbonate, bone waste porcelain powder, plant straw powder, aluminum hypophosphite, sodium antimonite, halloysite nanotube and waste foam concrete. Through cooperation of ammonium fluoroborate, basic magnesium carbonate, melamine polyphosphoester, aluminum hypophosphite and sodium antimonite, inflaming-retarding property is excellent, fuming can be prevented, droppings are not generated, toxic gas is not generated, and safety and environment friendliness are realized; tephra, halloysite nanotube and bone waste porcelain powder improve the overall performance of the foam material, and the material is made high in practicality and long in service life.