Abstract: A redundant-parallel structure is proposed as an elastic-body structure of a six-axis force sensor with a wide range and a large force plate. Based on the global stiffness and deformation compatibility condition, an analytical method of hyperstatic force analysis for a six-axis force sensor with a redundant n-SS(n>6) parallel Stewart structure is presented. Further, the full mapping relationship between the axial forces of n branches and six-axis external forces is deduced. By analytically solving the generalized inverse of a block matrix, one uniform solution is acquired to compute the axial force at each branch whether the rigidities of all branches are uniform or not. Finally, numerical examples are employed to verify the correctness of the two methods mentioned above, which shows that the latter is succinct in form and easier to realize computer programming and also possesses significant application prospects.