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Аннотация Macroporous silicon with deep regular channels 3-4.5 mum in diameter was infiltrated with discotic and ferroelectric liquid crystals (LCs) at the temperatute of the isotropic phase and then the system was slowly cooled down to room temperature, with the liquid crystalline mesophase formed. The orientation of the LC molecules in the porous matrix was studied by FTIR spectroscopy. The alignment of LCs was ascertained by comparing the behavior of various vibrational bands of a liquid crystal introduced into the porous matrix with that for LC inside the bulk cells of planar and homeotropic alignment. The molecules of the discotic LC show a planar orientation of their column's axis with respect to the surface of the macroporous silicon wafer, i. e., are perpendicular to the channel axis. The long molecular axis of the ferroelectric LC is aligned with the pore walls, having homeotropic orientation with respect to the wafer surface. In a macroporous silicon matrix, both kinds of LCs show unexpected enhancement of the low-frequency vibrational bands. The financial support of Enterprise Ireland through the International Collaboration Program IC/2001/042, Russian State Program \glqq Nanostructures in Physics\grqq and St.Petersburg Science Center Program \glqq Low Dimensional Structures\grqq are gratefully acknowledged.