Disclosed is an apparatus for measuring an amount of current in battery cells. The apparatus includes: a plurality of resistors (R1, R2, and R3) connected in parallel; a main chip connected to both ends of one (R1) of the plurality of resistors, detecting voltage across the connected resistor, and adding up the amount of current on the basis of the detected voltage; a multiplexer selecting one of the other resistors (R2 and R3) when the amount of current added up at the main chip exceeds a predetermined threshold value; and a plurality of switches connected to the plurality of resistors respectively, and switched on/off by an output signal of the multiplexer. Thereby, it is possible to prevent damage to the surrounding components caused by the generation of heat from the single detection resistor, and detect a more precise amount of current in the battery cells.