Crystallization of IR frequency-doubling nanocrystals in chalcogenide glasses is a promising approach to achieve novel nonlinear optical materials. However, controllable glass crystallization remains challenging. In this study, IR-transparent chalcogenide glass-ceramics containing novel Cd4GeS6IR frequency-doubling nanocrystals (about 60-80 nm) are fabricated through controlled nano-crystallization. Nanocrystalline structure of the Cd(4)GeS(6)nano-crystallized glass-ceramics is investigated in detail through X-ray diffractometer, field emission scanning electron microscope, and Raman scattering techniques. The structural similarity of [Cd4GeS6] polyhedron in the network structure of as-prepared glass is found to be responsible for the nucleation of Cd(4)GeS(6)crystal. A unique microstructure of Cd(4)GeS(6)nanocrystals embedded GeS(2)phase-separated structure is discovered in samples thermally treated at high temperatures (370 degrees C and 380 degrees C). This study would not only shed more light on glass crystallization mechanism but also provide a feasible approach for the design and fabrication of new IR frequency-doubling materials through glass crystallization.