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Adsorption of methanol and ethanol on the clean Pt(111) surface was studied at temperatures between 80 and 130 K using polarization-modulation infrared reflection absorption spectroscopy (PM–IRRAS). It was shown that adsorption of methanol at 80 K leads to the formation of amorphous solid methanol, and fast crystallization of the amorphous phase occurs upon warming at 100 K. Vapour deposition of methanol at 100 K directly leads to the formation of well-crystallized layers of solid methanol. According to PM–IRRAS, these crystalline layers consist of chains of hydrogen-bonded methanol molecules lying in a plane oriented close to the normal to the platinum surface. Adsorbed methanol is removed completely from platinum after heating to 120 K. Vapour deposition of ethanol at 80 K also leads to the formation of amorphous solid ethanol. However, subsequent warming does not lead to ordering of the adsorption layers, and at 130 K, ethanol is also completely desorbed.