The prevent invention relates to a functional mat (1) for assisting deep sleep of an infant. The functional mat (1) for assisting deep sleep of an infant, according to the present invention, comprises: a mat body (10) for supporting an object (100), which is the body of an infant, in the upward direction; a side supporter (30) protruding from the surface of the mat body (10) in the perpendicular direction so as to form an overall shape of a hill, thereby supporting the object (100) in the lateral direction; and a pressurizing supporter (50), which is positioned to intersect or cross in the width direction of the mat body (10), and which is fixed to the mat (1) and is forced against the object (100).