Next-generation sequencing technologies facilitate the analysis of multiple important properties of the transcriptome in addition to gene expression levels. Here we describe a method for mapping RNA 5' ends in Mycobacterium tuberculosis, which allows the determination of transcriptional start sites (TSSs), comparative analysis of promoter usage under different conditions, and mapping of endoribonucleolytic processing sites. We describe in detail the procedures for constructing RNA sequencing libraries appropriate for RNA 5' end mapping using an Illumina sequencing platform. We also outline the major steps of data analysis.