The combustion pressure characteristics of a turbocharged common rail diesel engine were experimentally investigated when using diesel/methanol compound combustion mode (DMCC). The combustion pressure characteristics were compared with the baseline engine, which including the related parameters such as the combustion pressure, the rate of pressure rise, maximum combustion pressure and combustion heat release rate. The results showed that, compared with the baseline engine, the form of heat release rate was changed significantly with DMCC mode, and the ignition point was simultaneously delayed a lot. Besides, the proportion of premixed combustion increased, and the proportion of diffusion combustion decreased. The results provided the theoretical basis for improving the efficiency and reducing the exhaust emissions of diesel engine by the DMCC mode.