This paper proposes applying optical wireless communications (OWC) for electrical equipment monitoring in high-voltage power grid. The fast development of power grid urgently requires reliable, efficient, and broadband wireless communication techniques for monitoring, protection, and control. High-voltage equipment and power-line, however, generate strong electro-magnetic (EM) field in its neighboring area. In this harsh environment, the performance of traditional radio-frequency (RF) wireless methods is significantly degraded, if not impossible. The authors developed an OWC system for this environment, which is able to satisfactorily solve the problem. Being different from the RF solutions, it uses light as the wireless information carrier to effectively resist electromagnetic interference (EMI). In order to further adapt this technique to the high-voltage situation, the authors developed and attached special isolation and self-powered supply modules to conventional OWC designs. The system was compared with a fiber system in the EM field of a 3kV converter. The results show OWC is able to provide satisfactory performance similar to a fiber system. In addition, it has exclusive advantages of being wireless, such as mobility, scalability and installation flexibility.