DAMPING FORCE VARIABLE TYPE SHOCK ABSORBER

A damping force variable type shock absorber includes: a piston rod reciprocating within the cylinder; a piston valve connected to the piston rod to partition the cylinder into a compression chamber and a rebound chamber; a housing including an auxiliary chamber communicating with a connection passage penetrating an inside of the piston rod in a longitudinal direction of the piston rod, the housing being connected to a lower portion of the piston valve and forming an auxiliary passage connected to the compression chamber disposed thereunder; a first damping unit disposed in an upper side of the auxiliary chamber to form a first bypass passage communicating the connection passage with the auxiliary passage in a zigzag form, the first damping unit allowing a deformation according to a flow of a working fluid in a predetermined speed section; a second damping unit accommodated in the auxiliary chamber and disposed under the first damping unit to form a second bypass passage connected to the first bypass passage, the second damping unit allowing a deformation according to the flow of the working fluid in a predetermined speed section; and a seal unit accommodated in the auxiliary chamber and disposed under the first damping unit to vertically support the second damping unit. Accordingly, it is possible to improve ride comfort by bypassing the working fluid while allowing a deformation along the flow of the working fluid in a predetermined speed section.