The invention relates to a germanium quantum dot growing method. The method includes the step that germanium quantum dots grow on a graphene layer. A graphene interface with the extremely high evenness is introduced to the surface of a conventional substrate, the Ge quantum dots grow on the interface, the condition that complex washing procedures are conducted on the conventional substrate in order to acquire the high-quality interface is avoided, and process procedures are simplified. The low impurity element content and the low defect density of the germanium quantum dots are guaranteed, the self-organizing growing process of the germanium quantum dots is guaranteed, and the germanium quantum dots which are uniform in shape and even in density are formed.