The goal of this study is to find out the acoustic features specific for ASD children vocalizations and speech. Three types of experiments were conducted: emotional speech, spontaneous speech, and the repetition of words. Participants in the study were children with ASD (F 84.0 according to ICD-10), biologically aged 5-14 years (n = 25 children) and typically developing (TD) children aged 5-14 years (n = 60). We compare acoustic features that are widely used in speech recognition and speech perception: pitch values, max and min values of pitch, pitch range, formants frequency, energy and duration. Formant triangles were plotted for vowels with apexes corresponding to the vowels [a], [u], and [i] in F1, F2 coordinates, and their areas were compared. For all children with ASD voice and speech is characterized by high values of pitch, abnormal spectrum, and well-marked high-frequency. Stressed vowels from the words of children (TD & ASD), spoken in discomfort, have higher values of pitch and the third (emotional