The current investigation was carried out during the two successive seasons of 2007/2008 and 2008/2009 in order to enhancement of seedling growth and produce vigorous transplants in African Mahogany by foliar application with ascorbic acid (0, 100, 200, 400 and 600 ppm). The obtained results revealed that most of the applied concentrations of ascorbic acid (200, 400 and 600 ppm) promoted significantly the investigated morphological characters (plant height, number of leaves/plant, total leaf area/plant, fresh weight of shoot/plant and dry weight of shoot/plant) of vegetative growth of African Mahogany (10 months old) and produced vigorous transplants in both studied seasons. The maximum promotion was achieved at 600 ppm ascorbic acid which in turn being statistically indifferent with the effect obtained by 400 ppm ascorbic acid in this concern. Likewise, the maximum significant increase in concentration of photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids) and of total sugars in leaves of African Mahogany plant aged 10 months was detected at 600 ppm ascorbic acid. Also, such treatment caused considerable thickness of the main stem of African Mahogany plant aged eight months by increasing thickness of both phloem and xylem tissues as well as by increasing diameter of pith. Likewise, average diameter of vessel was increased in treated plants to cope with vigorous growth induced by foliar application with 600 ppm ascorbic acid.