The invention relates to a shield structure of a rock drilling apparatus for dampening noise, the rock drilling apparatus comprising a feed beam whose one end is a drilling end, whereby the drilling end of the feed beam comprises a first shield part mounted immovably relative to the feed beam, and a second shield part mounted movably relative to the feed beam. A tubular shield flexible at least in its longitudinal direction is mounted between the shield parts, the shield being tightly attached by its ends to the first and the second shield part.