Provided are a quantum dot, a method of preparing the quantum dot, an optical member including the quantum dot, and an electronic device including the quantum dot. The quantum dot includes a core including indium (In), A1, and A2; and a shell covering the core. A1 is a Group V element, A2 is a Group III element other than indium, and the core includes a first region, and a second region covering the first region. The first region does not include A2, and includes indium and A1, and the second region includes indium, A1, and A2, and indium and A2 are alloyed with each other in the second region.