A linear compressor, comprising: a shell provided with a discharge port; a cylinder disposed in the shell, defining a compression space for a refrigerant to be compressed therein; a piston configured to reciprocate in an axial direction within the cylinder; a discharge valve disposed at one side of the cylinder to selectively discharge the refrigerant compressed in the compression space; a valve spring, including a plate spring, coupled to the discharge valve to provide a restoring force thereto; and a stopper (240, 240a) coupled to the valve spring to restrict deformation of the valve spring, wherein the stopper comprises: a stopper body for supporting the valve spring when the valve spring is deformed and contacts the stopper; a spring support provided at a periphery of the stopper body to support the valve spring in its undeformed condition, so as to allow the stopper body to be spaced apart from the valve spring; characterized in that the stopper further comprises: a valve avoidance groove defined in a central portion of the stopper body to prevent the stopper body from interfering with the discharge valve in its open position; and a guide (246, 246a) recessed in a direction in which the valve spring is deformed so as to reduce an impulse between the stopper and the valve spring when the valve spring is deformed and contacts the stopper, wherein the guide (246, 246a) extends between the spring support and the valve avoidance groove, wherein the guide (246, 246a) comprises a contact surface that is configured to contact the valve spring when the valve spring is deformed, wherein the contact surface comprises a rounded surface or a slanted surface that extends at an incline with respect to a radial direction perpendicular to the axial direction. a shell provided with a discharge port; a cylinder disposed in the shell, defining a compression space for a refrigerant to be compressed therein; a piston configured to reciprocate in an axial direction within the cylinder; a discharge valve disposed at one side of the cylinder to selectively discharge the refrigerant compressed in the compression space; a valve spring, including a plate spring, coupled to the discharge valve to provide a restoring force thereto; and a stopper (240, 240a) coupled to the valve spring to restrict deformation of the valve spring, wherein the stopper comprises: a stopper body for supporting the valve spring when the valve spring is deformed and contacts the stopper; a spring support provided at a periphery of the stopper body to support the valve spring in its undeformed condition, so as to allow the stopper body to be spaced apart from the valve spring; characterized in that the stopper further comprises: a valve avoidance groove defined in a central portion of the stopper body to prevent the stopper body from interfering with the discharge valve in its open position; and a guide (246, 246a) recessed in a direction in which the valve spring is deformed so as to reduce an impulse between the stopper and the valve spring when the valve spring is deformed and contacts the stopper, wherein the guide (246, 246a) extends between the spring support and the valve avoidance groove, wherein the guide (246, 246a) comprises a contact surface that is configured to contact the valve spring when the valve spring is deformed, wherein the contact surface comprises a rounded surface or a slanted surface that extends at an incline with respect to a radial direction perpendicular to the axial direction. a stopper body for supporting the valve spring when the valve spring is deformed and contacts the stopper; a spring support provided at a periphery of the stopper body to support the valve spring in its undeformed condition, so as to allow the stopper body to be spaced apart from the valve spring; characterized in that the stopper further comprises: a valve avoidance groove defined in a central portion of the stopper body to prevent the stopper body from interfering with the discharge valve in its open position; and a guide (246, 246a) recessed in a direction in which the valve spring is deformed so as to reduce an impulse between the stopper and the valve spring when the valve spring is deformed and contacts the stopper, wherein the guide (246, 246a) extends between the spring support and the valve avoidance groove, wherein the guide (246, 246a) comprises a contact surface that is configured to contact the valve spring when the valve spring is deformed, wherein the contact surface comprises a rounded surface or a slanted surface that extends at an incline with respect to a radial direction perpendicular to the axial direction. a valve avoidance groove defined in a central portion of the stopper body to prevent the stopper body from interfering with the discharge valve in its open position; and a guide (246, 246a) recessed in a direction in which the valve spring is deformed so as to reduce an impulse between the stopper and the valve spring when the valve spring is deformed and contacts the stopper, wherein the guide (246, 246a) extends between the spring support and the valve avoidance groove, wherein the guide (246, 246a) comprises a contact surface that is configured to contact the valve spring when the valve spring is deformed, wherein the contact surface comprises a rounded surface or a slanted surface that extends at an incline with respect to a radial direction perpendicular to the axial direction.