Spectral patterns of ATP, ADP and AMP in the infrared region are described. The presence of absorption zones typical for the monophosphate was found in 580 cm-1, 650 cm-1, 680 cm-1 and a double zone at 720--730 cm-1. This enabled to identify the substnace in the mixture with other nucleotides with an error about 10%. Effect of binding of phosphate groups on the position of the absorption zones of NH+4 and OH- at 3000--3600 cm-1 and occurence of the typical for P--O--P absorption zone at 910 cm-1 were established.