Blind cord resistance adjustment structure and blind

A blind cord resistance adjustment structure, comprising a cord-winding shaft assembly, an adjustment block (3) and a blind cord (4), wherein the cord-winding shaft assembly comprises a housing (21), a rotating shaft (22) and a shaft sleeve (23), the shaft sleeve (23) is rotatably mounted in the housing (21) along a circumferential direction of the shaft sleeve, the shaft sleeve (23) is sleeved on the rotating shaft (22) and rotates synchronously with the rotating shaft (22), an upper end of the blind cord (4) is connected to the shaft sleeve (23), and the adjustment block (3) is slidably arranged on a lower side of the housing (21) along a horizontal direction or a substantially horizontal direction, a first through-hole (210) for the blind cord (4) to pass through is provided on the housing (21), a second through-hole (31) for the blind cord (4) to pass through is provided on the adjustment block (3), at least one elastically deformable deformation portion (32) is provided on the adjustment block (3), first positioning teeth (321) are provided on the deformation portion (32), and a plurality of first positioning grooves (211) corresponding to the first positioning teeth (321) are provided on the housing (21), and the plurality of first positioning grooves (211) are distributed along a sliding direction of the adjustment block (3).