Abstract: The present invention relates to an open-cell foam composition, a hydrophobic open-cell foam prepared using the composition, and a method for preparing the hydrophobic open-cell foam. Specifically, the present invention provides an open-cell foam composition and a method for preparing a hydrophobic open-cell foam having hydrophobicity/oleophobicity and improved heat resistance as a result of partially or completely coating the surface of the inner framework structure of an open-cell foam, prepared using the composition, with silica gel, in which the method comprises continuously and efficiently preparing a melamine foam from a resin.