Simpson-Golabi-Behmel syndrome (SGBS) is an X-linked disorder caused by a mutation of the glypican-3 gene. The physical characteristics associated with SGBS have been documented in several papers, but information on the behavioral phenotype is scarce. We report on the speech and language characteristics in an 8 year-old-boy with SGBS. The boy performed very well on formal language tests but he also demonstrated poor pragmatic skills. Speech was characterized by a distorted articulation, distorted resonance, fluency failures, and a stereotype prosody. Many more case descriptions are necessary to delineate the full range of the behavioral phenotype of SGBS.