Method and apparatus for fusion splicing optical fibers

A method of fusion splicing optical fibers. Cores of the optical fibers to be fusion spliced are arranged in such a manner that the ends of the corresponding cores of optical fibers opposingly face to each other between discharge electrodes for fusion splicing. Discharge current flowing between the discharge electrodes is automatically adjusted according to a number of the cores of the optical fibers to substantially provide an optimal correction to the discharge current in relation to the number of the cores of the optical fibers. The discharge current is further adjusted to a variation in atmospheric pressure to substantially provide an optimal correction to the discharge current in relation to the variation in atmospheric pressure.