Single-phase AgGaGeS4 polycrystalline materials were synthesized directly from the constituent elements by vapor transporting and mechanical oscillation method. The problem of explosions was solved by careful control of the heating and cooling cycle and adopting the two-zone rocking furnace with specially designed temperature profile. The mechanical and temperature oscillations, as well as gradient cooling, were introduced in the synthesis process. The X-ray diffraction (XRD) analysis and Energy Dispersive Spectrometer (EDS) micro analysis indicated that the synthesized compound is a single-phase AgGaGeS4 polycrystalline material.