Abstract: Yongle Bell is the largest bell in China. The experimental study On Yongle Bell has been carried out in two aspects: modal analysis and characteristics of bell sound. A method for modal analysis under transient-state is presented in this paper. The lowest natural frequency of Yongle Bell is 16 Hz. The sound of bell is harmonious. The frequencies of some partial tones, which are important in sensation, conform with the standard scale.