Abstract: Objective To report three-year-old twin brothers with speech stunting.Methods The clinical program of twin brothers with speech stunting were reported.Results The development quotient of Neuropsychological Developing Table of 0 to 6 Years-Old Nurselings was 59 for elder brother,and 57 for the younger.PET showed hypogenesis in the frontal lobe.Their linguistic rating showed both speech stunting,and the brain-audition evoked potential and the autistic evaluation(ABC and CARs)were normal.Conclusion The etiology of twin brothers' speech developing disorders is related with heredity,brain development,and speech environment,but the exact cause is being further studied.

Key words: twin brothers, speech stunting, etiology, frontal lobe hypogenesis