Gelfand-Kirillov dimension of Poincar e-Birkho-Witt ( PBW for short) extensions was established by Matczuk ((15), Theorem A). Since PBW extensions are a particular example of skew PBW extensions (also called PBW extensions), the aim of this paper is to compute this dimension for these extensions and hence generalize Matczuk's results for several algebras which can not be classied as PBW extensions.