In the past few decades, thanks to the continuous development of machine learning and deep learning algorithms, as well as the continuous improvement of computing power and databases, facial recognition technology (FRT) has developed rapidly. Widespread use of this technology can be seen in all fields of life, such as facepay, individual identification, smart-city surveillance, e-passport or even face to DNA identification. However, some experts believe that certain errors that commonly creep into its functionality and a few ethical considerations need to be addressed before its most elaborate applications can be realized. This article explores the ethical issues of FRT used in different scenarios, tries to examine some legal and regulatory issues that may be encountered during the use of FRT, and technically analyze how to build a trustworthy intelligent system.