A system for setting the minimum output current of an LED dimming power supply, comprising: an initial value setting module, a data detection module, a data processing module, an output adjustment module, a DC / DC current output module electrically connected with the output adjustment module, a load connected in series at the output of the DC / DC current output module, and an output regulation module, characterised by the initial value setting module being configured to preset a threshold value of a minimum output rated current of the LED dimming power supply and tune a control signal output by the output adjustment module that controls an output value of the DC / DC current output module to the minimum, the data detection module being configured to detect a load current flowing through the load, the data processing module being configured to compare the load current with the threshold value and output a comparison result, the output adjustment module being configured to adjust the control signal according to the comparison result of the data processing module, while the load current is less than the threshold value, in order to adjust the output voltage of the DC / DC current output module, and make sure that the current value at the load is equal to the threshold value, the DC / DC current output module being configured to convert an input DC constant voltage into a DC constant current, and the output regulation module being configured to regulate the output value of the control signal of the output adjustment module when the load current is equal to the threshold value by adjusting the control signal of the output adjustment module. an initial value setting module, a data detection module, a data processing module, an output adjustment module, a DC / DC current output module electrically connected with the output adjustment module, a load connected in series at the output of the DC / DC current output module, and an output regulation module, characterised by the initial value setting module being configured to preset a threshold value of a minimum output rated current of the LED dimming power supply and tune a control signal output by the output adjustment module that controls an output value of the DC / DC current output module to the minimum, the data detection module being configured to detect a load current flowing through the load, the data processing module being configured to compare the load current with the threshold value and output a comparison result, the output adjustment module being configured to adjust the control signal according to the comparison result of the data processing module, while the load current is less than the threshold value, in order to adjust the output voltage of the DC / DC current output module, and make sure that the current value at the load is equal to the threshold value, the DC / DC current output module being configured to convert an input DC constant voltage into a DC constant current, and the output regulation module being configured to regulate the output value of the control signal of the output adjustment module when the load current is equal to the threshold value by adjusting the control signal of the output adjustment module.