A dynamic balance type vertical vibration isolator includes slide blocks, balance springs, mass blocks, a fixed block, rotation shafts, stiffness-adjustable springs, etc. When an earthquake force is upward, the stiffness-adjustable springs are compressed, upward forces of the stiffness-adjustable springs are increased, meanwhile, the slide blocks and the mass blocks move away from the fixed block, the balance springs are stretched to generate pull forces, and the pull forces have vertically upward components, so as to reduce compression degrees of the stiffness-adjustable springs, and further to reduce the upward forces of the stiffness-adjustable springs. Similarly, when the earthquake force is downward, the stiffness-adjustable springs are stretched, downward forces of the stiffness-adjustable springs are increased, meanwhile, the slide blocks and the mass blocks move close to the fixed block, the balance springs are compressed to generate compression forces, and the compression forces have vertical downward components.