Abstract: Numerical simulations of the incompressible ideal magnetohydrodynamics (MHD) equations involve the coupling of multiple physical fields, including the fluid velocity, magnetic field, and electric field. Due to the strong nonlinearity and multi-physics interactions inherent in the system, designing robust and accurate numerical methods is a significant challenge. Traditional numerical approaches often struggle to preserve physical conservation properties, such as mass conservation and charge conservation at the discrete level, which can compromise the long-term stability and physical fidelity of the simulations. In this work, we propose a high-order, strictly mass-conserving mixed finite element discretization for the incompressible ideal MHD equations. Our method introduces a velocity-vorticity-magnetic formulation by incorporating the evolution equation for vorticity. For temporal discretization, we adopt the implicit midpoint method and construct a temporally staggered grid. Furthermore, we apply an explicit-implicit splitting strategy to the coupling terms, which allows the entire system to be fully decoupled and avoid the need for iterative solvers typically required by nonlinear systems. The proposed scheme demonstrates optimal spatial convergence rates in three-dimensional convergence test. In the classical two-dimensional Orszag-Tang vortex simulation, the divergence-free condition of the velocity field is maintained at machine precision, with only rounding errors present. These results confirm the stability, accuracy, and structure-preserving capabilities of the proposed method in capturing complex MHD phenomena.