The invention relates to a high-precision cylindrical sleeve inner wall closed special-shaped curved slot detecting device which is especially suitable for precise detection of the work curved surface of an inner wall closed special-shaped curved slot. The device comprises a workpiece spindle transmission system, a lathe bed, a depth feed shaft transmission system, a linear feed shaft transmission system, a detecting device, a numerical control system and an inductive micrometer. By linkage of a linear feed shaft and a workpiece spindle, the data of the inductive micrometer is collected and saved in a computer, precise detection of the work curved surface of the cylindrical sleeve inner wall closed special-shaped curved slot is achieved, and the machining precision requirements for the work curved surface of the high-strength and high-rigidity inner wall closed special-shaped curved slot can be satisfied.