Abstract: Arc faults easily occur in dc microgrids due to the presence of many lines and equipment interfaces, and the arc can be divided into series arc and parallel arc according to the connection between arc and circuit. In order to realize arc fault detection and location effectively, it is necessary to study the characteristics of arc fault signal in DC microgrid. In this paper, a simulation and experimental platform of DC microgrid arc faults is built, and different locations and types of arc faults are generated. Moreover, the influences of DC/DC converter and line transmission on the arc signal characteristics and signal propagation are analyzed and verified through the current response of the microgrid system to arc faults. The findings indicate that the voltage clamp, current recovery, filtering and switching noise caused by DC/DC converter, as well as the signal crosstalk and signal attenuation caused by line transmission, make the arc detection in DC microgrid system more difficult.