The numerical simulation of groundwater flow is an important method for evaluating groundwater resources. As researches go further, urgent requirements have been posed on modeling large-scale groundwater with much-refined spatial grids and long temporal series which will lead to heavy computation burden for effective solving groundwater partial differential equation. As a result, the use of the serial computing could slow down calculating rate of the model, and even lead to incorrect running of the model because of the limitation from the memory and the data channel bandwidth of the software. This research introduces and investigates recent developments (MPI, OpenMP, and PETSc) in the parallel solution of groundwater simulation partial differential equation to allow larger problems to be solved. The results showed that multiple processors to cooperatively work can solve the large-scale groundwater flow equations and permit the use of a finer resolution grid that leads to greater precision in the solutions.