B-cell chronic lymphocytic leukemia (CLL) is the most common human leukemia occurring as indolent or aggressive form. CLL clinical features and genetic abnormalities are well documented, but molecular details are still under investigation. MicroRNAs are small non-coding RNAs involved in several cellular processes and expressed in a tissue-specific manner. MicroRNAs regulate gene expression, and their deregulation can alter expression levels of genes involved in development/progression of tumors. In CLL, microRNAs can function as oncogenes or tumor suppressors and can also serve as markers for CLL onset/progression. Here, we discuss the most recent findings about the role of microRNAs in CLL and how this knowledge can be used to identify new biomarkers and treatment approaches.