The invention provides a shifting fork mechanism for driving a fluid sliding ring. The shifting fork mechanism comprises a fluid sliding ring flexible connection device and two shifting forks; the fluid sliding ring flexible connection device comprises a corrugated pipe, an outer connecting pipe and the fluid sliding ring; one end of the corrugated pipe is connected with a flowing channel openingin the outer circle of the fluid sliding ring, the other end of the corrugated pipe is connected with the outer connecting pipe, and the outer connecting pipe is fixed to a rotating tower table; the two shifting forks are arranged symmetrically and each comprise a fixing support lug, a small connecting rod, a large connecting rod and a fluid sliding ring support lug which are hinged sequentially;and the non-hinged ends of the fixing support lugs are welded to a vertical column, the vertical column is a part of the rotating tower table, and the non-hinged ends of the fluid sliding ring supportlugs are welded to the outer circle of the fluid sliding ring. Under rotation driving of the rotating tower table, the shifting forks drive the outer circle of the fluid sliding ring to rotate freely. According to the shifting fork mechanism for driving the fluid sliding ring, the problems of eccentric abrasion, vibration, abnormal sound and the like in the rotation process of the fluid sliding ring under the severe sea condition are solved.