The invention provides a shield structure cutter head mud cake cutting device and cutting method, and relates to the field of shield structure mud cake cutting. The shield structure cutter head mud cake cutting device comprises a high pressure jet device. The high pressure jet device comprises an auto-rotating type sprayer and a barrel body which are installed on a cutter head. The auto-rotating type sprayer is connected with the front end of the barrel body through a main shaft assembly. The main shaft assembly comprises a main shaft. A water channel I is arranged on the side wall of the barrel body. A water channel II is arranged on the front end of the barrel body. The front end of the main shaft is of a hollow structure provided with a water channel III. The water channel I, the water channel II and the water channel III communicate with one another sequentially. A water inlet of the auto-rotating type sprayer communicates with the water channel III. The auto-rotating type sprayer on the device provides rotating power by utilizing reactive force when water flow rushes out, a mud cake is cleaned by 360 degrees with no dead corner through two high pressure column sprayers arranged on the sprayer, cleaned muck falls into an excavation bin and is discharged with a mud pipeline, and practicability is good.