A linear compressor comprising: a shell; a cylinder provided in the shell to define a compression space for a refrigerant; a frame coupled to the outside of the cylinder; a piston provided to reciprocate in an axial direction within the cylinder; a motor providing power to the piston; and a spring device connected to the piston and configured to allow the piston to resonate; wherein the spring device comprises: a support coupled to the piston and comprising a spring support having one or more of insertion holes; a first coupling protrusion extending along an edge of each of the insertion holes on a rear surface of the spring support; a support cap inserted into the insertion hole; a first resonant spring fitted into an outer surface of the second coupling protrusion; and a second resonant spring fitted into an outer surface of the first coupling protrusion, wherein the support cap comprises: a body inserted into the insertion hole; a seating surface extending from one end of the body in a radial direction so as to be closely attached to the front surface of the spring support; and a second coupling protrusion protruding toward a front surface of the spring support from the seating surface, characterized in that: the body has the other end passing through the insertion hole, wherein a tapered part is provided on an outer surface of the other end of the body, and wherein a guide surface that is inclined to gradually decrease in diameter from the front surface of the spring support to the rear surface is provided on the edge of the insertion hole. a shell; a cylinder provided in the shell to define a compression space for a refrigerant; a frame coupled to the outside of the cylinder; a piston provided to reciprocate in an axial direction within the cylinder; a motor providing power to the piston; and a spring device connected to the piston and configured to allow the piston to resonate; wherein the spring device comprises: a support coupled to the piston and comprising a spring support having one or more of insertion holes; a first coupling protrusion extending along an edge of each of the insertion holes on a rear surface of the spring support; a support cap inserted into the insertion hole; a first resonant spring fitted into an outer surface of the second coupling protrusion; and a second resonant spring fitted into an outer surface of the first coupling protrusion, wherein the support cap comprises: a body inserted into the insertion hole; a seating surface extending from one end of the body in a radial direction so as to be closely attached to the front surface of the spring support; and a second coupling protrusion protruding toward a front surface of the spring support from the seating surface, characterized in that: the body has the other end passing through the insertion hole, wherein a tapered part is provided on an outer surface of the other end of the body, and wherein a guide surface that is inclined to gradually decrease in diameter from the front surface of the spring support to the rear surface is provided on the edge of the insertion hole. a support coupled to the piston and comprising a spring support having one or more of insertion holes; a first coupling protrusion extending along an edge of each of the insertion holes on a rear surface of the spring support; a support cap inserted into the insertion hole; a first resonant spring fitted into an outer surface of the second coupling protrusion; and a second resonant spring fitted into an outer surface of the first coupling protrusion, wherein the support cap comprises: a body inserted into the insertion hole; a seating surface extending from one end of the body in a radial direction so as to be closely attached to the front surface of the spring support; and a second coupling protrusion protruding toward a front surface of the spring support from the seating surface, characterized in that: the body has the other end passing through the insertion hole, wherein a tapered part is provided on an outer surface of the other end of the body, and wherein a guide surface that is inclined to gradually decrease in diameter from the front surface of the spring support to the rear surface is provided on the edge of the insertion hole. a body inserted into the insertion hole; a seating surface extending from one end of the body in a radial direction so as to be closely attached to the front surface of the spring support; and a second coupling protrusion protruding toward a front surface of the spring support from the seating surface, characterized in that: the body has the other end passing through the insertion hole, wherein a tapered part is provided on an outer surface of the other end of the body, and wherein a guide surface that is inclined to gradually decrease in diameter from the front surface of the spring support to the rear surface is provided on the edge of the insertion hole. the body has the other end passing through the insertion hole, wherein a tapered part is provided on an outer surface of the other end of the body, and wherein a guide surface that is inclined to gradually decrease in diameter from the front surface of the spring support to the rear surface is provided on the edge of the insertion hole.