Magnetic induction tomography(MIT) is a noninvasive and contactless medical imaging technique. The 16 channels of MIT system is showed in the paper, which image for the low conductivity object with working at 1MHz. In the study, we use the water tanker filled with salt solution and the different conductivity agar blocks to simulate the human brain with edema or hematoma. The each sensor is composed of the excitation coil, the two detection coils, a preamplifier board and a power amplifier board, which were fixed by four plastic columns. This paper researches the sensitivity and stability of single sensor unit, and the phase sensitivity of the system is 0.29°/S·m-1 and the phase drift is in the range of -0.02° to +0.06° over 30 minutes. Finally, the 2-dimensional images of conductivity distribution are obtained using the inverse distance weighted spatial interpolation algorithm of and the direct projection way.