This study presents a robust kernel-based collocation method (KBCM) for solving multi-term variable-order time fractional partial differential equations (VOTFPDEs). In the proposed method, Radial basis functions (RBFs) and Muntz polynomials basis (MPB) are implemented to discretize the spatial and temporal derivative terms in the VOTFPDEs, respectively. Due to the properties of the RBFs, the spatial discretization in the proposed method is mathematically simple and truly meshless, which avoids troublesome mesh generation for high-dimensional problems involving irregular geometries. Due to the properties of the MPB, only few temporal discretization is required to achieve the satisfactory accuracy. Numerical efficiency of the proposed method is investigated under several typical examples.