The working principle of the laser induced breakdown spectroscopy (LIBS) is interpreted. A LIBS experimental setup is developed based on Nd∶YAG laser and CCD grating spectrometer. Several experiments were carried out to study the effect of laser pulse energy, delay time and pressure. Atomic spectra was obtained using lower pulse energy; The best S/N could be realized by adjusting the delay time; Some samples could be induced to breakdown without strong continuum background; Emission signal with good S/N could be obtained at low pressure(5×10-5Pa), but the signal intensity was lower than at air pressure. The standard atomic spectra could be obtained by carrying out LIBS analysis of pure samples in the sample chamber, and the elemental recognition of unknown samples could be realized by comparing their atomic spectra with the standard spectra, in which the system recognition error was avoided.