The present invention relates to a damper comprising : a housing formed with a piston space and a configuration space capable of filling a working fluid; a piston movably disposed in the piston space; and a piston rod connected to the piston to be exposed from the outside of the casing and capable of moving. A first outer casing flow path and a second outer casing flow path are formed along the length direction of the outer casing around the piston space. A first piston flow path and a second piston flow path are formed along a longitudinal direction of a portion of the outer peripheral portionof the piston. A first flow regulating flow path for connecting the first outer casing flow path and the first piston flow path and a second flow regulating flow path for connecting a second outer casing flow path and the second piston flow path are formed along an outer circumferential portion of the piston in a circumferential direction.