Background and Aim: Hearing impairment affects all aspect of individual life, specially language and communication skills. When hearing impairment is congenital or occurs early in life, the child's ability to learn optimally through audition, will be affected. The aim of this study was to evaluate linguistic skills of preschool hearing impaired children and compare these skills with normal peers.

Methods: This descriptive cross-sectional study was performed on 38 preschool hearing impaired children that the main handicap was severe to profound hearing loss with ability to communicate orally and 28 normal children with the same cultural and social context. Twenty four non linguistic variables including age, gender, the age of entrance of preschool center, number of hearing aids, etc. were obtained by filling a questionnaire and fifteen linguistics variables including number of utterance, morphemes, correct utterance, noun phrase, ambiguous utterance, correct sentences, compound sentences, etc. were collected by some part of TOLD-P-3 test and three complementary questions. Then we compared the data from two groups.

Results: There were significant differences between number of utterance, number of correct mean length utterance, number of well-formed sentences in normal and hearing impaired group (p<0.000). There were no significant difference between unintelligible utterances, repetitive utterances and bad-formed sentences between two groups(p>0.05).

Conclusion: This study showed a severe deficit in linguistic skills in preschool hearing impaired children.