Experimental investigations on anti-aliasing properties of acoustic low-pass filtering fiber-optic hydrophones are reported. Acoustic low-pass filtering fiber-optic hydrophones is a novel kind of fiber-optic sensors, which is proposed to eliminate the aliasing in fiber-optic hydrophone arrays. Theoretical and experimental results show that it has good acoustic low-pass filtering properties, and can restrain the high frequency interference strongly. Effects of high freqeuncy interference on demodulation results of fiber-optic hydrophones without acoustic filter and anti-aliasing properties of fiber-optic hydrophones with acoustic filter are studied experimentally. Results show that fiber-optic hydrophones without filter cannot work normally when the high frequency interference is strong, while the acoustic low-pass filtering fiber-optic hydrophones still work well. The demodulation results of acoustic low-pass filtering fiber-optic hydrophone are in good agreement with the results without interference, and the correlation coefficient of the demodulation acoustic signals is higher than 0.99. Acoustic low-pass filtering fiber-optic hydrophones provide an effective solution to the aliasing existing in modern photoelectric sonar systems.