The invention belongs-the field of building materials, and discloses an environmentally-friendly lightweight foam brick for buildings, and a production method thereof. The foam brick is produced from, by weight, 40-60 parts of silicate cement, 10-20 parts of waste glass, 20-30 parts of enteromorpha, 15-25 parts of seashells, 10-20 parts of building masonry wastes, 10-20 parts of expanded perlite, 1-2 parts of an early strength agent, 0.2-0.5 parts of glycerol polyoxyethylene ether, 2-3 parts of lanolin, 0.2-0.4 parts of sodium dodecylbenzenesulfonate, 1-2 parts of gelatin, 0.3-0.5 parts of disodium ethylene diamine tetraacetate, 6-10 parts of potassium silicate, 0.3-0.5 part of sodium lignosulfonate, 0.6-1 part of alkylphenol polyoxyethylene ether, 0.5-0.8 part of sodium dehydroacetate and 1-2 parts of fluorinated-silicated acrylate. The foam brick produced in the invention has the advantages of energy-saved and environmentally-friendly raw materials, closed and spherical pores and good comprehensive strength.