The paper is devoted to experimental study of laser cleaning of plaster. Nowadays laser technologies are widely used in the preservation of Cultural Heritage, and laser cleaning is most frequently used technique in artworks conservation. However, laser cleaning of plaster sculptures and architectural decorations is not yet established. Experimental results of divestment of model samples and 20th century plaster sculpture by means of pulsed Nd:YAG laser (generating at wavelengths of 1064 nm, 532 nm and 355 nm) and fiber laser with wavelength of 1064 nm are presented.