In this work, we report a comprehensive study on developing high performance magnesium phosphate cement (MPC) composite bipolar plates for fuel cells. The MPC composite bipolar plates composed of MPC with partial replacement of fly ash as the binding matrix phase and multiple carbon-based materials (including graphite, carbon fiber and multi-walled carbon nanotubes) as the conductive phase. A simple hot-press process was applied to produce the MPC composite. After the optimization on the formula and the structure of the MPC composite and the processing parameters, all the US DOE 2015 technical targets, including electrical conductivity, flexural strength, corrosion resistance were achieved as well as low cost. Finally, the performance of the as-prepared MPC composite bipolar plates was investigated via a three-single-cell stack of passive-type direct methanol fuel cells. The performance test results indicated that the MPC composite bipolar plates were capable of fuel cell applications.