The invention discloses a current control and system monitoring device of a module-type DC power supply system, which comprises a plurality of power supply modules, a current detecting module and a monitoring module, wherein each power supply module respectively receives alternating current and converts the alternating current into direct current to be outputted according to control data. All of the power supply modules are connected in parallel and together output the generated DC current to a load. The current detecting module detects the value of the current outputted from the module-type DC power supply system to the load so as to output current detecting value. The monitoring module receives the current detecting value which is compared with a current set value for analysis to reset the current set value, and form another control data transmitted to every power supply module according to the reset current set value, thus, the output current value of the module-type DC power supplysystem and the anticipated current set value are gradually consistent.