Differing from civil engineering and construction, landscape architecture projects are far from efforts in operation and project management. Under the circumstances, it is worthwhile to adopt scope definition from project management for construction and civil engineering in some respects. First, scope definition is able to be conducted through a simple procedure without additional investment in capital and time. Second, the output produced by scope definition is very substantial. The research scrutinized scope definition procedures accompanied by landscape architecture project execution and derived various methods in order to help scope definition for efficient landscape architecture projects. Based on the literature review, a design case study, and an exert interview, the project success elements were developed consisting of 3 sections, 8 categories and 50 elements, grounded on the theoretical base of PDRI. The elements are expected to pave a way to an adequate level of scope definition among participants of landscape architecture projects and contribute in efficient project execution.