The utility model relates to a dynamic synchronous distributor of hydraulic cylinders, which comprises a master cylinder and a plurality of auxiliary cylinder groups in the corresponding number to external working cylinders. Each auxiliary cylinder group comprises n auxiliary cylinders, and n is greater than or equal to 2. The size of the cylinder meets the condition that the sum of one-stroke flow of the n auxiliary cylinders in the same group is equal to the one-stroke flow of the corresponding external working cylinders. The plunger of the master cylinder is connected with the plunger of each auxiliary cylinder to achieve synchronous motion. The hydraulic oil receiving pipe of the master cylinder is connected with one oil path of a hydraulic power cabinet, and the hydraulic oil receiving pipes of the individual auxiliary cylinders in the same group are connected with the one-end chambers of the corresponding external working cylinders. The dynamic synchronous distributor is applied to distribute hydraulic oil to a plurality of hydraulic cylinders that are in coordinated operation, and ensures that a plurality of external hydraulic cylinders in coordinated operation can meet the requirement for complete dynamic synchronization all the time during the whole operation process. The dynamic synchronous distributor has the advantages of stable operation, simple structure and high operating reliability.