The performances of inorganic airborne molecular contaminants (AMCs) via silica gel tubes, impingers, and diffusion denuder sampler (DDS) were compared in a cleanroom. The results showed silica gel tubes were not applicable for cleanroom sampling due to high blanks. While with optimal sampling conditions both impingers and DDS have much better performances, of which DDS has the lowest detection limits of the method for HF, HCl, HNO2, HNO3, SO2, and NH3 gases to be 0.15, 0.11, 0.13, 0.03, 0.07, and 0.42 mu g/m(3), respectively. Results indicated no significant difference for the HF and SO42- concentrations made by the DDS and impingers.