A device to extract elements contained in cavities, that uses a bag for their extraction and an applier The invention relates to a device for extracting elements from cavities, which uses: a bag for extraction, which folds in on itself and an applicator provided with an air chamber. According to the invention, the bag includes pockets, into which the tentacles of the applicator are inserted, and pull means. The applicator is formed by a first piece, known as the outer tube, which is a hollow tube of rigid material, having a distal end forming at least two tentacles that provide radial flexibility and a proximal end provided with means for attaching the second piece, known as the inner tube, which is an open-ended hollow tube that slides inside the body of the outer tube and has a funnel on the distal end thereof. The device may also include graduated scales on the tentacles, the inner tube and the bag. In addition, the bag has two reference rings on each one of the folds thereof.