Numerical simulation of the Ni-like Mo x-ray laser at 189 nm (4d→4p, J=0→1) pumped by grazing incidence pulses is performed using a modified one-dimensional hydrodynamic code MEDUSA. By comparing the electron density, the electron temperature, and the absorbed laser energy density obtained by the grazing incidence and the normal incidence schemes respectively, it is clearly shown that the absorption efficiency is greatly increased in the grazing incidence scheme due to the increased absorption of driver laser in the gain region.