Fragile X syndrome (FXS) is one of the most prevalent forms of heritable mental retardation and developmental delay in males. It is caused by a defective gene on the X chromosome. The syndrome is caused by the silencing of a single gene (fragile X mental retardation-1; FMR1) and the lack of expression of its protein product (fragile X mental retardation-1 protein; FMRP). Expansion of the CGG repeat is associated with changes in the amounts of FMR1 mRNA and protein and with varied phenotypes. Full mutation alleles (>200 repeats) are associated with gene methylation and transcriptional silencing, which cause fragile-X syndrome. It is associated with a wide spectrum of physical, behavioral, cognitive, and language problems. 20 participant males with FXS (full mutation) exhibit atypical language during conversational interactions as evidenced by poor receptive language, expressive language, semantics, pragmatics and prosody. Magnetic resonance imaging was used to assess cortical morphology and gray and white matter volume to find out the relation between language and brain morphology in FXS, it showed correlation between the whole right and left hemisphere which have strong association for auditory language perception.