In this article, we first report a facile solvothermal route, via using green and phosphine-free oleic acid (OA) as the solvent, to synthesize flowerlike α-In 2 Se 3 architectures assembled by two-dimensional (2D) nanosheets. This synthetic approach requires no precursor pre-synthesis or toxic compounds. The formation mechanism of the flowerlike α-In 2 Se 3 structures was discussed in detail. This simple synthetic route may provide a new possibility in the challenge of preparing other metal selenides with nanostructures. These as-prepared flowerlike α-In 2 Se 3 nanostructures exhibit a strong room-temperature photoluminescence emission in NIR region excited at 320nm, which might offer a kind of novel alternative functional nanomaterials in the field of photovoltaic cells, bioimaging, and biolabeling.