Pharmaceutical composition exhibiting effects of preventing decrease in white blood cells and restoring white blood cells, containing angelica gigas nakai extract as active ingredient

The present invention relates to an Angelica gigas Nakai extract and, more specifically, to an Angelica gigas Nakai extract having effects of preventing a decrease in the number of white blood cells and restoring the number of white blood cells, containing decursin and decursinol angelate as active ingredients. Preferably, the Angelica gigas Nakai extract of the present invention contains 70 wt% or more of decursin and decursinol angelate.