A shock absorber includes a first damping force generating portion, and a second damping force generating portion. The second damping force generating portion includes a first flow path, an opening and closing member, an adjustment unit which adjusts a position of the opening and closing member in the axial direction, a second flow path which is located at a different position from the first flow path and passes through the piston in the axial direction, and a second valve which is disposed at an end portion of the second flow path at a side of a second end portion which is an end portion at an opposite side to the first end portion in the axial direction, and which opens and closes the second flow path.