A drilling jig for surgical drilling tools is disclosed. The drilling jig comprises two sleeves of identical design mounted alongside each other on a common holder, with each sleeve being mounted on the holder so as to be pivotable in relation to each other about an axis of rotation extending perpendicular to their respective longitudinal axes. Each sleeve is hollow to allow a drilling tool to pass through. At the rear end of each sleeve is a stop surface for the drilling tool to rest against, the stop surface delimiting the depth to which the drilling tool penetrates the sleeve. Each sleeve is of two-part design and includes a bearing part and an adjusting part, with the bearing part carrying the front end of the sleeve and the adjusting part carrying the stop surface. The bearing part and the adjusting part are threaded to each other in such a manner that the spacing between the stop surface and the front end of the sleeve is adjustable by turning the adjusting part in relation to the bearing part, which enables alteration of the effective length of the sleeve without removing the drilling tool.