The invention discloses an armored cable small-diameter bent spherical regulating device based on an elastic ring. The armored cable small-diameter bent spherical regulating device comprises a cable tube inlet and a cable tube outlet, wherein a spherical cable bending mechanism is arranged between the cable tube inlet and the cable tube outlet; the spherical cable bending mechanism is formed as follows: a fixed half ball is buckled on a movable half ball, and combined surface rotation is set between the two half balls; the combined surface rotation between the two half balls refers to that a radial slot is formed in the combined surface of the fixed half ball, a convex ring is arranged in the combined surface of the movable half ball, the elastic ring is arranged at the periphery of the convex ring, and the elastic ring is placed in the radial slot and fixed with the convex ring. A collision bead is arranged on the combined surface of the two half balls. According to technical scheme adopted by the invention, the armored cable small-diameter bent spherical regulating device is low in cost, simple in structure, convenient to use and capable of realizing bending of armored cables or other cables within a range of 0-90 degrees.