FeAlPO-16 molecular sieve with AST topologyhas been ionothermally prepared under microwave irradiationin succinic acid-choline chloride eutectic mixture forthe first time. The structure and morphology of FeAlPO-16molecular sieve are characterized in detail by powder X-Raydiffraction (XRD), Fourier transform infrared spectroscopy(FT-IR), diffuse reflectance UV–visible (UV–vis) spectroscopy,thermogravimetry–differential scanning calorimetryanalysis (TG-DSC) and scanning electron microscopy(SEM). UV–vis results suggest that iron species may partiallyenter the framework of FeAlPO-16 molecular sieve.SEM images indicate that large spherical particles observedin the images are agglomerates of FeAlPO-16 molecularsieve nanocrystalline (ca. 100 nm in size). Effects of synthesisconditions, such as P2O5/Al2O3 ratio, pyridine/Al2O3ratio, reaction temperature and crystallization time, as wellas iron and aluminum source on the crystallization ofFeAlPO-16 molecular sieve are systematically investigated.Experiments show that FeAlPO-16 molecular sieve canbe prepared over a wide molar ratio of Al2O3:xP2O5:yPyridine:0.4Fe2O3:58EU (x = 1.0–3.5, y = 0.8–7.8) usingaluminum isopropoxide and ferric ammonium citrate asiron and aluminum source, respectively. The synthesis ofFeAlPO-16 molecular sieve is highly sensitive to ironsource, but not to aluminum source, crystallization temperatureand time.