[en] The increasing applications of different types of lasers in medicine, industry, data acquisition, and nano technology are based on the study of interaction of laser with matter. In this paper, several experiences on the effects of laser beam with the surfaces are investigated. The main interactions of laser with matter are: photochemical process, photo ablation, thermal effect, plasma induced ablation and photo distribution, which depend on exposure conditions and thermal and optical properties of material. The thermal response of the interaction of low power He-Ne laser with tissue and the results of rapid treatment of ophthous by low power diode laser are reported. The thermal effects of CO₂ laser on the skin of mouse has been also reviewed. The measurement of photo ablated absorption cross-section for two different types of polymers (PMMA and polycarbonate) by ArF excimer laser is reported and plasma induced ablation by Q-switched Nd-YAG laser on the uni nary calculi has been studied and the threshold of photo distribution has been measured too