It is an old experience that emotions modify the human voice, the speech style. Autobiographical recall and music was used in this study to induce sad and happy emotional states. Participants told happy, natural and sad stories about themselves, and half-minute-long periods of each story were analysed phonetically with the program Praat. The authoress studied how speech parameters like duration of silent pauses, rate of the pauses to the whole speech, articulation rate, fundamental frequency and its variety, intensity and its variety were modified by emotions. Results show that emotions have measurable effects on speech. A tendency-level difference was found between sad, natural and happy emotional states. Calculating with the parameters one at a time significant differences were found: in sad emotional states intensity and rate of articulation decreased, further duration of pauses and their relation to the whole speech extended, compared with the happy states. Compared with the natural state there was only one significant difference: rate of articulation decreased.