Magnesium diboride (MgB2) was successfully produced in a pellet with sandwich-like structure. The sample was prepared by embedding a layer of Mg powder in between layers of boron powder before they were cold-pressed and sintered in argon atmosphere at different temperatures. After sintering, the interfacial regions between the Mg and B layers were examined and hexagonal platelets were observed lying along the interfacial regions in samples sintered at temperatures above 700°C. These hexagonal platelets were confirmed as MgB2. When samples were sintered at higher temperatures, the lateral size of the platelets increased. At 700°C, the average size of the platelets was 0.5 μgm, and it increased to 1.5 μgm in sample sintered at 900°C. In addition, the critical temperature (TC) and the magnetization (M) were also changed from 35.4 K to 37.1 K and −0.7 to −1.8 emu/g, respectively.