In the field of antenna measurement, in order to evaluate the performance of the antenna in the actual working environment, more and more attention has been paid to on-site antenna measurement technology. The technology of on-site testing and evaluation of antenna performance indicators with the help of Unmanned Aerial Vehicle (UAV) has made significant progress in recent years. The current UAV-based antenna measurement systems can be divided into two types, one is to directly measure the antenna pattern, gain and other indicators under far-field conditions, and the other is to obtain far-field antenna indicators by data transformation after near-field measurement. This paper summarizes the research status of UAV-based antenna measurement systems, and proposes an outfield UAV measurement scheme. The feasibility of the system is verified by the outfield test experiment of the radiation pattern of the S-band standard gain horn antenna, and the measurement error is further analyzed.