In this paper, the magnetic exploration technology is applied to the geomagnetic anomaly analysis of hollow ferroconcrete cylinders. By using the method of volume integral, the analytic equations of various components of the geomagnetic anomaly are formulated. And then the central section, the planar isogram and the three-dimensional map of the geomagnetic anomaly vertical component Za are drawn. Furthermore, the distribution features of the magnetic anomaly are detected. In addition, this paper has analyzed inversion problems on the height and the site of hollow ferroconcrete cylinder, and studied the relationship between the altitude of magnetic survey and the magnetic anomaly. The results are theoretically and practically useful in archaeology, engineering exploration and such military fields as the reconnaissance and anti-reconnaissance of this type of objects.