Summary: High-throughput RNA sequencing (RNA-seq) is rapidly emerging as a major quantitative transcriptome profiling platform. Here we present DEGseq, an R package to identify differentially expressed genes or isoforms for RNA-seq data from different samples. In this package, we integrated three existing methods, and introduced two novel methods based on MA-plot to detect and visualize gene expression difference. Availability: The R package and a quick-start vignette is available at http://bioinfo.au.tsinghua.edu.cn/software/degseq Contact: XW: xwwang@tsinghua.edu.cn; XZ: zhangxg@tsinghua.edu.cn. Supplementary information: Supplementary data are available at Bioinformatics online. 10.1093/bioinformatics/btp612