This study discusses tsunami characteristics around Taiwan through Fast Fourier Transform (FFT) and Hilbert-Huang Transform (HHT) methods based on collecting tide data during Tohoku earthquake on March, 11-13 2011. Tsunami is one of the most destructive forces on earth and it can cause serious loss of life and property damage. Most tsunamis are generated by earthquake on the seafloor. A tsunami is a global event where its waves produce in one side of the ocean were observed in another side of the ocean. Tide data with tsunami signal obtained by observation are usually non-stationary and non-linear. Hilbert-Huang Transform (HHT) has the capability to find out the characteristic of the non-linear and non-stationary signal. HHT consists of two steps: first is to decompose the data using EEMD then calculate spectral using Hilbert Transform. Six stations are chosen to represent different parts of Taiwan. Analysis results show that similar tsunami frequencies are detected in all stations. This work shows that HHT can reveal the Tsunami arrival on energy-frequency-time plot and time period of Tsunami.

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