A new approach is described for calculating the induced current and field in the human body by high-voltage alternating electric fields. The distribution of the electric field is obtained by using Laplace's equation. This relates the surface charge induced on the body to the potential in a reciprocal Laplace problem, which is then calculated by charge simulation method coupled with genetic algorithms to determine the appropriate arrangement of simulating charges inside the human body. The presented model for simulating electrical field is a three dimensional field problem and introduced different types of charges to simulate the different elementary geometrical shapes of human body. The particular strength of the charge simulation method in this application is its ability to allow a detailed representation of the shape and posture of the human body. The results have been assessed through comparison induced current and its distribution over the body surface, as estimated in other experimental and computational work. The accuracy of the simulated electric field is satisfied for the potential error (less than 0.1%), and the field deviation angle (less than 1°) over the human body.