Electromagnetic tomography（EMT） simulation system is acted as the object of study.Effect of position deviation of the detection coils and angle deviation on imaging result are discussed.Using average value of relative error

the maximum value of relative error and the minimum value of relative error as evaluation index

in two-dimensional space

the detection values caused by the coil axis displacement and the angle deflection are compared with the ideal values

and reconstructed images are given.It can draw a conclusion that when there are noise exists in measured data

the location of the reconstructed images will be close to edge of the object field

that is from near the coil sensor

which has practical meaning to correcting sensor model.