Abstract: The present invention relates to a fixing system for joints, finishing profiles or decorative profiles, which can be applied in the fixing of finishing profiles, decorative profiles or expansion joints, for use with wall coverings, ceilings, partitions or floor panels, and in the case of the latter whether they are stratified, ceramic, or made of natural stone or parquet. It is characterised in that it consists of three parts that are applied or manufactured jointly with the profiles. The male part 1 comprises an upper element 2 with a central indentation 3 for fitting into a cavity 11 which extends below the decorative or finishing profile 5; a lower element 6 with peripheral ridges 7 for fitting into the corresponding ridges of the base part 8; a shaft 10 which connects the two aforesaid elements. The female part or base part 8 is screwed or glued to the surface that is going to be covered and it is composed of an open rectangular gutter whose internal walls or sides are covered with ridges or furrows 9.