Various physicochemical methods, including infrared spectroscopy are applied for studying the structure and composition of activated carbons. The aim of the work was investigation of structure activated carbons obtained from nutshell after various heat treatment with use of IR spectroscopy method in KBr pellets. IR spectra were recorded on a FTIR Spectrometer Spectrum 100, PerkimElmer (2007) in the range of 4000-400 cm-1, and they are represented on the figure below.schemeIt was found that the substantial changes occurred in the carbons with temperature rising from 250 to 600С. With temperature raising a broad band with a maximum at 2077 cm-1 was appeared in the IR spectrum, that related to (CС) alkyne and v(C=C) allene structures. A typical intense band at 1620 cm-1, corresponding to v(C=C) of the benzene rings and graphite was observed [1]. A group of strongly intersecting bands was revealed in the region 1600-1200 cm-1 in the spectra of the activated carbons where the v(C=C) frequencies of the benzene rings are situated. An area of v(C-C) skeletal vibrations was presented the intensive intersecting bands forming the complex contour in the range of 1230-1080 cm-1. Contours of the spectra before and after heat treatment were different. It follows that at higher temperatures there are structural changes in activated carbons from nutshell.