Abstract: In order to survey standing wood volume,based on Kunze Trunk Curve Equation,the authors built another continuous trunk curve equation set to describe whole trunk form.At the same time,precision volume calculation equation by section was put forward.An improved tree accurate volume measurement equation of form point method had been thus deduced.They also worked out an upward deduction equation in form point height h₂to conquer difficulties in surveying form points,and increase the efficiency of forestry investigation. Therory and experiment have proved that under the precondition of setting the trunk volume surveyed by precision volume calculation equation by section as true number,compared with mid-area sectional measurement method of the volume and the old form point method,improved form point method is simple and operative,more accurate and practicable.