Abstract: A new ship detector known as the polarimetric notch filter (PNF) was developed in 2012 by Marino¹. No open literatures are found to compare the PNF with the classic polarimetric whitening filter (PWF). The probability density functions (PDF), the probability of false alarm (PFA) and the thresholds of the PWF detector are derived in closed forms in the inverse gamma-distributed textural product model case (G0-Wishart). The detection performances of the PNF are compared with those of the classic PWF via simulated data and real data from AIRSAR in Wishart case and G0-Wishart case. The results show that the performance of the PWF in ship detection is better than that of the PNF in most cases, while the adaptability of PNF is better than that of the PWF in high sea state case.