An adjustment mechanism for adjusting a formed staple height of a suture staple in a stapler comprises a first handle portion and a second handle portion. The first handle portion comprises a cartridge support located at a distal end, a cartridge assembly, a drive assembly, and the adjustment mechanism for adjusting a formed staple height of a suture staple, and the second handle portion comprises an anvil located at a distal end. The cartridge assembly comprises suture staples, and the drive assembly can drive a suture staple to leave the cartridge assembly to reach the anvil to be pressed and formed. The adjustment structure adjusts a distance between the drive assembly and the anvil to adjust a formed staple height of a suture staple in a stapler. This application further relates to a stapler, comprising the adjustment mechanism for adjusting a formed staple height of a suture staple in a stapler.