Fuel cell start control system and control method therefor

The fuel cell start control system includes a plurality of fuel cell stacks configured to generate power by receiving air and fuel, a power storage device connected to a bidirectional converter and configured to be charged by generated power of a respective fuel cell stack or configured to supply power, and includes a controller configured to control a start of a fuel cell stack among the plurality of fuel cell stacks which satisfies a start condition based on a fuel cell stack starting request, the controller configured to control a start of at least one fuel cell stack based on generated power of the fuel cell stack or charged power of at least one power storage device.