The influence of speaker's emotional factors on speech features is studied. The speech features of the same person such as voice formant frequency characteristics, formant trend characteristics, syllable transition characteristics, fundamental frequency curve characteristics and amplitude curve characteristics under six emotions such as anger, fear, happiness, neutrality, surprise and sadness are chosen. The similarities and differences of voice acoustic characteristics of different emotions are analyzed and compared. The results show that the similarity of formant orientation characteristics of the same person's speech acoustic characteristics under different emotions is high, and there are some differences in formant frequency, fundamental frequency curve and amplitude curve characteristics, which are non-essential differences, and are individual differences. Acoustic characteristics analysis of speech with different emotions can lay a foundation for speech emotion recognition.