A symbol rate detection apparatus includes an analog-to-digital converter (ADC), a coarse detection module, a mixer, a down-sampling module, and a fine detection module. The ADC converts an analog input signal to a digital input signal at an original sampling frequency. The coarse detection module estimates a carrier frequency offset and a coarse symbol rate according to the digital input signal. The mixer adjusts the frequency of the digital input signal according to the carrier frequency offset to generate a frequency-compensated signal. The fine detection module determines a fine symbol rate according to the frequency-compensated signal.