Abstarct: Airbone electromagnetic surveys are extensively used in mineral exploration, engineering activities, and enviromental investigations. These methods measure secondary field induced due to primary field varying with time. Then using this secondary measured field, we determine earth resistivity distribution. In our country these surveys are carried out in recent years. So it is necessary to interprete the results of the surveys. Available methods for interpretation are numerical modeling, approximate inversion and inversion methods with iterative calculation. In attention to results from various methods in helicopter electromagnetic data it is obviously seen that there is not a unique method that can show the depth and resistivity for entire underground models. For this reason more investigation for this purpose is needed. The purpose of this research is to recognize advantages and disadvantages of available modeling methods in face of different synthetic models and finally choose one or more of them for the best in mentioned models. Approximate methods do not need an initial model for inversion and also are very fast in time. The methods used in this research are phase ratio, amplitude, Siemon, Niblett-Bostick and SUTHEM methods. In forward modeling for calculating complicated integral of earth, GuptaSarma and Singh method is used. The code related trhese methods is written in GUI with Matlab and a software for inversion prepared is used. Synthetic models involved are in one and two dimensions. One dimensional models are in homogenous half space and laxyered half space (two, three and four laxyers). Two dimension models are dipping conductive plate with different dips, dipping conductive laxyer, resistive and conductive dike (in finite and infinite state) and two anomalies near and under each other. Resistivity-depth profiles and two-dimensional cross-sections prepared for the above mentioned models. Pseudo-laxyer half-space method is better for approximate inversion in determining boundary of different areas. We can obtain more reliable resuls in determining depth and resistivity values using pseudo-laxyer half-space method. Niblett-Bostick method is the best in this case. Siemon and SUTHEM methods have similar results. The results of the phase ratio method for finite anomalies are better than one-dimensional profiles.