Abstract: The present invention discloses a two-degree-of-freedom and three-degree-of-freedom switchable ball joint structure, comprising: an outer shell with an accommodating cavity; a hollow sphere, which is located in the accommodating cavity of the outer shell and is rotatable in the accommodating cavity, wherein the lower hemispherical surface of the sphere is provided with a groove; a limiting pin, which is vertically inserted in the outer shell and located below the sphere, and the axis line of which passes through the center of the sphere; a first worm gear assembly, which is provided in the outer shell for driving the limiting pin to make a linear reciprocating motion in the vertical direction; wherein the first worm gear assembly drives the top of the limiting pin to be inserted into or exit from the groove to realize the adjustment of the degree of freedom of rotation of the sphere.