The present invention relates to a positioning device (1) for a medical field generator (2), comprising:&mdasha base member (3) which comprises at least one contacting section (3a) and is configured to contact the upper surface of an operating table&mdashan adaptor (4) which is connected to the base member (3) and configured to support the field generator (2) and&mdashfixing means (5) which allow the positioning device (1) to be fixed to an operating table, wherein the adaptor (4) is configured to prevent the field generator (2) from being positioned at less than a predetermined distance from the operating table. The present invention also relates to a method for positioning a medical field generator (2), comprising the following steps:&mdashproviding a medical field generator (2) and a positioning device (1) as described above&mdashattaching the field generator (2) to the positioning device (1)&mdashpositioning a base member (3) of the positioning device (1), with the field generator (2) attached to it, on the upper surface of an operating table and beneath a part of a patients body, in particular the head of a patient lying on the operating table&mdashfixing the positioning device (1) to the operating table.
