A phase tracking device. A sampler samples the received signal according to a sampling frequency correction signal to generate a first signal. A phase de-rotator adjusts the phase of the first signal according to a carrier frequency correction signal to generate a second signal. A fast Fourier transformer performs a fast Fourier transformation on the second signal according to a symbol edge to generate a third signal. An equalizer equalizes the third signal according to the estimated channel to generate an output signal. A selector selects the output signal which meets the predetermined condition. A phase error metric processor generates the correction signals for both sampling clock frequency offset and carrier frequency offset according to the selected sub-carrier indexes and their corresponding phase error metrics and channel estimates.