Zinc selenide (ZnSe; mineral name: stilleite) and its nanostructured composite (ZnSe/C) are prepared by simple solid-state synthetic routes, and their potential as electrode materials for rechargeable Li-ion batteries is investigated. The reaction mechanism between ZnSe and Li is demonstrated using ex situ X-ray diffraction and extended X-ray absorption fine structure analyses. The X-ray diffraction patterns and high-resolution transmission electron microscopy observations confirm that ZnSe nanocrystallites in ZnSe/C are uniformly distributed within an amorphous carbon matrix. The nanostructured ZnSe/C composite electrode exhibit excellent electrochemical performances such as a high capacity and long cycling behavior of ca. 705 mAh g−1 over 300 cycles.