The results of the study on the regeneration of mangrove tree species, Avicennia officinalis L, under conditions of different flooding levels, 10, 20, 30 cm during 12 hours, resembling to diurnal variations, showed that no disparities in the survival rate were experienced as compared to control. Moreover, if there are intervals of none flooding interacted the regeneration ability of this tree species is normally high. It is also noted that there is the significant differehce of growth in height of them. From these results some thinking could be suggested that is the rise in sea level occurred by climate change does not have effects on growth and regeneration of mangrove tree species. The sea level may increase 30 cm higher due to climate change in future as compared to present time the diurnal variations do not have effects on growth and regeneration of mangrove forests.