A light string controlling circuit for single node and a method thereof are provided. The light string controlling circuit for single node includes a plurality of light-emitting elements, a power source element, a master controller and a plurality of single-node controllers. The master controller outputs a power supplying request to the power source element to instruct the power source element to supply power to the plurality of light-emitting elements sequentially. The plurality of single-node controllers are connected to the plurality of light-emitting assemblies respectively, and each of the single-node controllers outputs an emission control signal to control the luminous state of the corresponding light-emitting assemblies.