A province in the central China faces the problem of energy shortage, 800kV Mengxi UHVDC project will effectively broaden the energy input channels of the province, enhance energy supply security, and reduce the pressure on coal transportation. This paper analyses the load, power supply and power shortage of a central province, and explored the role of Mengxi UHVDC project played in improving the energy demand in the Central China power grid. By comparing the different access plans to the grid, this paper demonstrated that it’s more appropriate to divide the Mengxi UHVDC into 1000kV and 500kV at the inverter side for consuming the power of UHVDC and protecting the normal power supply.