Variable joints are the crucial structures for changing topological characteristics of variable topology mechanisms. Design of variable joints is a challenge for the type synthesis of variable topology mechanism. Based on the concept and method of design catalogue,the design catalogues of variable joints were proposed to design the structures of variable joints. Adopting the arithmetic operation of constraint functions,the constraint variation features of variable joints were described in the three processes of topological variations (including changing the axis azimuth,changing the numbers and changing the types),respectively. Based on summarizing and designing the corresponding variable structures of general joints,the design catalogues of variable joints were established through classifying and compiling the design information,including the ways of topological variations,constraint variation features,and structures of variable joints. Meanwhile,the example shows that the design catalogues of variable joints are applicable to design the structures of variable joints for variable topology mechanisms effectively. This method provides convenience for type synthesis of variable topology mechanisms with variable joints.