Abstract: In recent years, laser ablation technology combined with single or multi collector inductively coupled plasma mass spectrometry (LA-(MC)-ICP-MS) has been widely used to analyze the isotopic compositions of solid rock and ore mineral samples by means of aerosol transported to inductively coupled plasma mass spectrometer after micro sampling by laser ablation system, which has the advantages of in situ, real-time, fast, and nondestructive analysis and its high spatial resolution, high sensitivity, simultaneous determination of multi-element and its isotope ratios. This paper introduced a series of in situ micro-analytical methods of isotopic compositions developed and established by the author′s laboratory in recent years, mainly including boron isotopic composition of boron-rich minerals such as tourmaline and muscovite, carbon isotopic composition of carbonate minerals, sulfur isotopic composition of sulfide and sulfate minerals, strontium isotopic composition of strontium-rich minerals such as apatite and hafnium isotopic composition of zircon, as well as U-Pb dating methods of cassiterite, wolframite, monazite, titanite and garnet.