The invention provides a repeatable switch sliding sleeve mechanism for a casing sliding sleeve. The repeatable switch sliding sleeve comprises a shell, a sealed sliding sleeve and a lower sliding sleeve; a liquid outlet hole is formed in the upper portion of the shell; the sealed sliding sleeve and the lower sliding sleeve are both arranged in the shell; the liquid outlet hole and a part of the sealed sliding sleeve are overlapped; the upper end of the lower sliding sleeve is sealed in a lower hole of the sealed sliding sleeve; an annular groove is formed in the inner wall of the upper portion of the sealed sliding sleeve; the sealed sliding sleeve and the lower sliding sleeve are connected through a closed shear pin; the lower sliding sleeve and the shell are fixedly connected through anopening shear pin; a first groove is formed between the sealed sliding sleeve and the lower sliding sleeve and formed below the closed shear pin; and a diameter-variable control ring is arranged in the first groove. The repeatable switch sliding sleeve mechanism further comprises a locking structure; a first part of the locking structure is arranged on the lower portion of the inner wall of the shell; and a second part of the locking structure is arranged on the lower sliding sleeve. The problems that an existing casing sliding sleeve tool cannot be closed, and a completion pipe string cannotkeep the full bore are solved, and the construction cost of shaft treatment, layer plugging and the like of an oil-gas field in the later period can be effectively reduced.