The sensitivity and linearity of eddy-current sensor are affected mainly by the distribution of the electromagnetic field.A simulation model of eddy-current sensor is created by means of finite element method（FEM）

utilizing the ANSYS language.At first

a physical model is set up

material characteristics is defined and the areas are meshed

then the border conditions are established

finally loading and solving are made.A existing theoretic formulary is used to validate correctness of the model at the same time.Computing three kinds of coils with different parameters

a study and analysis on how the coil structure affects the sensitivity and linearity of eddy-current sensor is made from the results.Experiment shows that the theoretical model of eddy-current sensor can be valuable for design of coil of eddy-current sensor.