Inorganic nanoparticles have been applied in various applications owing to their interesting properties including magnetic, thermal, optical, and catalytic performance. They can be classified as mono‐metallic nanoparticles, bimetallic nanoparticles, metal oxide nanoparticles, and quantum dots. Field‐flow fractionation (FFF) is an interesting nonchromatographic technique for size characterization of materials with nanometer range. Various subtechniques of FFF including flow, sedimentation, electrical, and thermal are described with some selected applications reviewed. Moreover, FFF can be used via off‐line and on‐line with many elemental detection techniques: GFAAS, ICP‐OES, ICP‐MS, and SP‐ICP‐MS to provide more information in term of quantification and element‐specific detection. In this article, applications of FFF with atomic spectrometric detection for various types of samples, including consumer products, food, environmental samples, biological samples, and sensors, are discussed.