The invention discloses a device for detecting the concave and convex amount of an upper edge plate of a stator blade of an aeroengine casing and an inner flow passage surface of the aeroengine casing. The device comprises a positioning assembly, an adjusting assembly and a sensor assembly; the adjusting assembly comprises a first vertical adjusting rod, and the first adjusting rod is provided with a second adjusting rod capable of moving in the vertical direction; the second adjusting rod is horizontally arranged and provided with a fixing assembly capable of horizontally moving on the secondadjusting rod; a fixing piece and two positioning bearings form a triangular structure for fixing an aeroengine casing assembly; the sensor assembly comprises a sensor, one end of the sensor is a sensing head, and the sensing head penetrates through the first adjusting rod and is in contact with one end of a connecting piece; the connecting piece is arranged at one end of a transmission rod, a rotating pin shaft is arranged in the middle of the transmission rod, and the other end of the transmission rod is connected with a horizontal lever part. The device can accurately detect the concave and convex amount of the upper edge plate and the inner flow passage surface of the aeroengine casing.