This paper describes briefly the technology of the measurement and interpretation of ground electromagnetic wave CT through the survey conducted in 7th ore body group of the Norbusa chromite deposit. The position, extension, strike and dip as well as the connection of ore bodies on cross-hole section can be detected and blind ore bodies on cross-hole section can also be found by ground electromagnetic wave CT. The test results prove the feasibility and effectiveness of the electromagnetic wave CT in the exploration of chromite deposits.