Abstract: Foothill area is one of the essential research objects of landscape planning. The effectiveness of spatial management and control in foothill area are influenced by complex factors such as multiple management and control subjects and policies due to the characteristics of foothill area as a mountain and plain ecotone. Identifying the influencing factors of spatial management and control is a crucial challenge for efficient management and scientific planning of foothill area. Taking the northern foot of Qinling Mountains in Xi’an as an example, this research implements an in-depth interview with several planning managers and technicians based on relevant methods and procedure of grounded theory, encodes and analyzes interview results by MAXQDA software, constructs a classification model for influential factors of spatial management and control in foothill area in Xi’an from the two dimensions of the relationship between technology and policy and its changeability thereof, and finally obtains three influential factors: changeable-technical (planning factors), changeable-nontechnical (cognitive, systematic, institutional and situational factors), and immutable-nontechnical (background factors). Based on this, the research further summarizes that object cognition, management and control system, and planning formulation are key technical factors influencing the spatial management and control in foothill area in Xi’an, and proposes such suggestions as establishing a guideline for spatial management and control featuring the superposition of two factors of nature conservation and land use based on the ecological security pattern, which provides a theoretical basis for the in-depth integration of landscape architecture disciplines into the territorial spatial planning of foothill area.