The invention provides a skin treatment device comprising a laser source (40) and focusing optics (50), such that a focal spot (18) is positioned in a dermis layer (24) of the skin to be treated. The laser beam (42) is powered and focused (16) such that a LIOB (laser induced optical breakdown) phenomenon is obtained, which affects the skin in order to stimulate re-growth of tissue. This in turn reduces wrinkles (30). The device may comprise wrinkle-determining means (52, 54, 56, 58). The focusing optics (50) may have a numerical aperture of at least 0.4. The invention also provides a corresponding method to treat skin, in particular to reduce wrinkles (30), by providing a focused laser beam (16) that causes LIOB in the dermis layer (24) of the skin. The advantage is that damage to overlaying epidermis layers may be avoided by the use of the very local LIOB phenomenon.