Recently, analytical sciences are more and more often tasked with the detection and characterization of nanoparticles by other scientific fields, such as biology and materials science, or by the industry. As recent studies have shown, laser-induced breakdown spectroscopy (LIBS) is an analytical method that can perform this task efficiently. This chapter overviews the basic methodologies and performance characteristics of LIBS in applications requiring the determination of the distribution, concentration, or composition determination of nanoparticles in gaseous, liquid, or solid samples. Examples of the described techniques include the analysis of aqueous colloids, aerosols, and biological tissues.