Abstract: The effects of ambient turbulence on rise of bent-over plumes have been analysed by use of an entrainment model in which an inflow component is assumed proportional to the characteristic velocity of ambient turbulence. The analysis demonstrates that the ambient turbulence shows notable.influence upon rising path of plume even in the early stages of rise and the leveling-off map occur relatively quickly. Better correlation between observed and predicted rise has been obtained fox buoyant plumes relased into non-stratified atmosphere. It has been found that both the dimensionless distance where the plume path begins to level-off and the dimensionless rise are sensitive to turbulence intensity. The validation of some plume rise formulas has been made.