The capacitive response of deep Fe acceptors in a semi‐insulatingn‐type Fe‐doped InP Schottky barrier has been investigated. The capacitance‐voltage (C‐V) and conductance‐voltage (G‐V) characteristics over the frequency range 0.06–100 kHz are measured at 300, 317, and 335 K. Great frequency dispersion is observed inCandG. The reverse bias dependencies ofCand (G−G0) are shown to be very weak at high frequencies, whereG0is the dc conductance. As measuring frequency is lowered, (G−G0) decreases butCincreases considerably. At low frequencies, the bias dependencies ofCand (G−G0) are observed and measured 1/C2versus reverse bias curves are found to be straight lines. It is shown that at low frequencies,Cand (G−G0) take maxima near zero bias and rapidly decrease in a forward bias region. As temperature increases, the frequency region in which such low‐frequency characteristics are found extends more widely into a high‐frequency range. Theoretical calculations ofCand (G−G0) are also carried out. The results are compared with experimental ones. Observed variations ofCandGwith frequency, bias voltage, and temperature are well explained in terms of the delayed response of deep Fe acceptors.