The invention provides a compression amount adjustable dynamic seal structure. The compression amount adjustable seal structure comprises a first inner piston block, a second inner piston block, a first seal ring, a second seal ring and two sets of installation rings. The first seal ring is installed on the rear side of the first inner piston block through the installation ring, and the second seal ring is installed on the rear side of the second inner piston block through the installation ring. The first inner piston block and the second inner piston block are axially and fixedly connected side by side and are in sliding fit with the inner surface of a hydraulic cylinder or a pneumatic air cylinder. The first seal ring and the second seal ring are made of elastic materials and can be compressed and deformed, and therefore the first seal ring and the second seal ring play a sealing role. The compression amount adjustable dynamic seal structure can be widely used for dynamic seal of a piston in the hydraulic cylinder or the pneumatic cylinder. The dynamic seal structure is provided with two seals, the sealing effect is more reliable, meanwhile, the compression amounts of the two seals are adjustable, and the service life of a sealing ring can be prolonged while the sealing performance is improved.