The behavior of magnesite during hot pressing is studied from 80$0^{circ}C$ to 110$0^{circ}C$ by Knoop hardness test, X-ray diffraction and electron microscopy. The growth of magnesia crystallite in magnesite is observed at 110$0^{circ}C$ and crystallite size is about 2 microns. It is also observed that hot pressing showes enhanced sinterability comparing to ordinary pressure-less sintering. The magnesia body with 95 per cent of theoretical density is obtained by hot pressing at relatively low temperature such as 110$0^{circ}C$.