The 3D green quantity is one of the important indexes to measure urban green space’s ecological bene t, which is essential to urban green space planning and construction. So it is of considerable signi cance to study the green quantity measurement technology. In this paper, the technology and method of 3D green quantity by using UAV, both at home and abroad, are researched. Through comparing and analyzing the advantages and disadvantages of different measurement paths under the same equipment and site, a low-cost and ef cient three-dimensional green quantity measurement method is put forward for landscape architecture planning and plant research.