The utility model provides a submarine cable bending testing device. The submarine cable bending testing device comprises a driven wheel assembly, a driving wheel assembly and a driving assembly; the driven wheel assembly comprises at least two driven wheels different in diameter and a main shaft vertically mounted on the ground; the driven wheels are rotatably and coaxially stacked on the main shaft; the driven wheels are all arranged horizontally; the driving wheel assembly comprises a driving wheel guide rail mounted on the ground, a driving wheel carrier, a motor mounted on the driving wheel carrier and a driving wheel mounted on the output end of the motor; the driving wheel is arranged horizontally; the driving wheel carrier is slidably mounted on the driving wheel guide rail by use of a liftable driving wheel truckle seat; the driving assembly comprises a bearing portal, a lift cylinder inserted in the top of the bearing portal, a main oil cylinder arranged transversely and a counter-force lever; the main oil cylinder is mounted in the bearing portal in such a manner of sliding up and down; the cylinder body part of the main oil cylinder is connected with the telescopic end of the lift cylinder; the telescopic end of the main oil cylinder is connected with one end of the counter-force lever by use of a cross beam, while the other end of the counter-force lever is connected with the driving wheel carrier. The submarine cable bending testing device is applicable to inspecting a submarine cable.