The invention relates to a safety alarming device applied in a monorail conveyor for a hillside orchard. The safety alarming device comprises a cardan joint (1), a pressure sensor (2), a photoelectric switch (3), a rail (4), a blocking metal circular plate (5), a supporting device (6), a trailer (7), a buzzer (8), a PLC (programmable logic controller) (9) and a traction compartment(10), wherein the traction compartment (10) and the trailer (7) are respectively arranged on the rail (4); the PLC (9) and the buzzer (8) are arranged on one side of the trailer (7); and the trailer (7) is connected to the rail (4) through the supporting device (6). According to the safety alarming device disclosed by the invention, the pressure sensor and the photoelectric switch are used for detecting whether the conveyor is overloaded or not, and whether the conveyor exceeds a safe inclination angle or not, so that the safe and smooth operation of the monorail conveyor for the hillside orchard can be effectively guaranteed.