Electromagnetic wave CT logging technology using CT receiver receives the data to reconstruct image, getting geological information, but the data that contains noise will seriously affect the quality of the reconstructed image, so filtering data efficiently has become a key link of the electromagnetic wave CT imaging. Because of the traditional way to get data is deeply affected by noise, proposed taking short quick sampling method to obtain data for each channel, constructed threedimensional matrix by the data, then decomposed it into twodimensional matrix, using the weighted moving average procession point by point. According to the method of filtering by limiting arithmetic average, the former one has a better filtering performance in smoothing data in the aspect of recovering data, and overcomes the disadvantage that the method of filtering by limiting arithmetic average will have more serious distortions. It can support more exact data for the crosshole electromagnetic wave detection.