Practical significance: a comparative analysis of the lexical speech development of preschoolers with mental disorders and preschoolers with the norm of speech development is carried out.The following features were found in children with mental disorders: very low cognitive activity, the predominance of substitution and suffixing in the formation of possessive adjectives, difficulties in selecting the appropriate word, ignoring less pronounced features when describing the subject; poor passive and active vocabulary, inaccuracy of the subject and verb vocabulary, difficulties in updating the dictionary, frequent use of neologisms.