AFI-type structure ferroaluminophosphate zeolite (FAPO-5) was examined as an AHP adsorbent. FAPO-5 with iron content of 2-8 mol% (Functional Adsorbent Material-Zeolite 01; FAM-Z01) was selected for further testing. The water vapor adsorption isotherm of FAM-Z01 was S-shaped and highly dependent on temperature, and almost no hysteresis was observed with adsorption/desorption at 333 K and 348 K. No changes were observed in the properties of FAM-Z01 after 200,000 cycles of water vapor adsorption-desorption, indicating that FAM-Z01 is suitably durable for practical use. When the AHP was operated under conditions of T-L/T-M/T-H = 283 K/303 K/333 K, the adsorption capacity of FAM-Z01 was 4 times that of silica gel.