A combined interpretation of magnetotelluric and gravity data recorded onland Mallorca is presented. The magnetotelluric data consist of five stations along a NW-SE profile across the island which periods ranging from 256 Hz to 200 s. An electrical model has been obtained taking into account the 3D sea effect. The gravity data consist of the Bouguer anomaly from which the residual contribution of the sedimentary formations has been obtained. A 3D modeling of this residual anomaly shows a good agreement with the MT model. The results of the combined interpretation of the gravity and magnetotelluric data provide constraints to the crustal structure of the island which is representative of the whole Balearic promontory. ¿ American Geophysical Union 1995