Small RNA (sRNA) is a class of non-coding RNA of 50-500 bases with a regulatory function on transcription, translation and mRNA stability. Bacterial sRNAs have been implicated in gene expression, cellular proliferation, virulence and adaptation to environmental conditions. The role of sRNAs in intracellular infection (such as Salmonella, Listeria, Legionella pneumophia, etc.), including the regulation on growth, virulence and host iron levels is reviewed in this paper.