Power Line Communication (PLC) covers a wide range of functions and has low cost. With the development of smart grid, new requirements of high-frequency spectral efficiency and large access capacity are put forward for power line communication. This paper studies the power line communication technology based on adaptive SCMA. Through adaptive modulation, SCMA technology can better adapt to the characteristics of strong signal attenuation, background noise and impulse noise in power line channel, and improve the spectral efficiency and user capacity in power line communication.