A foam sheet includes a polylactic acid resin composition that includes a polylactic acid resin and inorganic particles. The polylactic acid resin includes 98 mol % or greater of D-lactic acid or L-lactic acid that is a constituent monomer unit of the polylactic acid resin. An amount of the polylactic acid resin is 98% by mass or greater relative to a total amount of organic matter of the foam sheet. The inorganic particles include grains of sheet silicate. The grains of the sheet silicate have a mean volume diameter of 10 μm or greater and 200 μm or less, and an aspect ratio of 10 or greater and 100 or less. An amount of the grains of the sheet silicate in the foam sheet is 2% by mass or less.