An apparatus for signal acquisition of a Global Navigation Satellite System (GNSS) receiver may downsample digitalized satellite signals based on a code resolution, correlate the downsampled satellite signals and oversampled pseudo-random noise (PRN) codes using a block unit based on a size of a matching filter, and may perform FFT of a value output as a correlation result by employing, as M points, a number of blocks used for the matching filter. Also, the signal acquisition apparatus may estimate a coarse Doppler and a code phase of the satellite signals by comparing a power value, calculated based on the M-point fast Fourier transformed value, with a threshold value, and may estimate a fine Doppler using zero-padding based FFT when the satellite signals are successfully acquired.