Squaric acid catalyzed three-component Mannich reaction of aromatic aldehydes, aromatic amines and cyclic ketones in water and solvent-free conditions at room temperature. This protocol has several advantages such as good yields, mild conditions, novel organocatalyst, and good anti selectivities. Squaric acid catalyzed three-component Mannich reaction of aromatic aldehydes, aromatic amines and cycloketones in water and solvent free reaction conditions at room temperature. This protocol has several advantages such as good yields, mild conditions, novel organocatalyst, and good anti selectivities.