The aim of this study is to determine and describe acoustic parameters of voice in adults who stutter in order do determine its quality and to determine the impact stuttering has on the voice. Stuttering is defined as speech fluency disorder but its manifestatons can be observed on a wider domain than speech itself. It has impact on physical, physiological, social and emotional domain and in addition to all above, stuttering can have negative impact on the voice. Long-term misuse of the voice can have negative impact on its quality. In order to determine acoustic parameters, participants who stutter were tested on three tasks: vowel /a/ phonation, sylablle repetition and five sentences repetition. Speech samples were recorded in acoustically well-favored conditions without any noise distractions. After speech samples analysis and determination of acoustic parameters in Praat programme, further processing of the results was done in programme IBM SPSS Statistics 25 for statistical processing of the data. Stuttering severity was defined by using Stuttering Severiy Instrument (SSI). Results of descriptive statistics show that there are deviations from norms in the voice of adults who stutter which are visible in variables of shimmer, diadochokinesis, voice onset time and vowel duration. There is no statistically significant difference between acoustic parameters and stuttering severity. Differences in values of acoustic parameters do exist when compared to the norms and it's necessary to further invesigate the impact stuttering has on the voice in order to get the whole picture the stuttering has on the life of a person who stutters.