Abstarct: The geophysical potential field separation refers to separate the regional and local anomalies from the superimposed anomaly. The Empirical mode decomposition (EMD) proposed by Norden E Huang is a kind of spatial and temporal filtering process in terms of the signal extremum characteristic scales. . it’s a new data analysis method that suitable to process non-stationary and non-linear data. Its power to filter and decompose data has earned it a high reputation in signal processing. Empirical mode decomposition is a time_frequency analysis method which can adaptive decomposition of complex signals. The decomposed component contains diffrents bands of frequencies from high to low, and the residual value is the signal trend component representing the signal averaged trend, that is similar to the rigion anomalies in the geophysical field. The empirical mode decomposition (EMD) method is an algorithm for the analysis of multicomponent signals that breaks them down into a number of amplitude and frequency modulated zero¬-mean signals, termed intrinsic mode function (IMFs). An IMF must fulfill two requirement: (1) the number of extrema and the number of zero crossings are either equal or differ at most by one; (2) at any point, the mean value of the envelope defined by the local maxima and the envelope defined by the local minima is zero. baxsed on this theory, using the EMD to separate the geophysical potential field was proposed in this article. When EMD is used for separation anomaly, the problem is to identify properly which IMFs contain residual characteristics. Certain mode will consist mainly residual, whereas other modes will contain regional and noise characteristics. Magnetic field anomalies are usually superposed large-scale structures and small-scale structures anomalies. Separation of these two categories of anomalies is the most important step in the data interpretation. Different methods have been introduced for this work but, most of them are the semi¬-automatic methods, it means that interpretator’s opinion directly can affect the results. In this paper, empirical mode decomposition method is used to separate regional and residual magnetic anomalies. EMD decomposition results in what is “Residual”, which is similar to the regional anomaly of a potential field data. This residual does not require any preset parameters unlike contemporary field separation methods. This automatic method is baxsed on extraction of the intrinsic oscillatory modes of data. Efficiency of this method is investigated on both synthetic and real data acquired on north mahalat and Rodan area of province markazi and province hormozgan for region subsurface geology with the purpose of geothermal reservers and mining exploration. Compared to the conventional method of trend analysis, the EMD method is with less artificial influence, and we needn,t set any parameters beforehand. Otherwise, it reflects the potential field intrinsic physical characteristics better.¬ Separation results show that this technique have higher accuracy than conventional methods like as polynomial fitting and has a good consistency with regions geology. finally results of the new method is compared with results of the upward continuation filter and observed that these results is matched with the upward continuation filter .