The catfish (Silurus lanzhouensis), a popular scaleless fish, is highly nutritious and of great commercial importance. However, transcriptome information related to growth traits in S.lanzhouensis are still unknown. In this study, muscle transcriptome data was used to study this issue by RNA-Seq. In total 44,176,578 to 52,345,588 raw reads were generated for each sample, 163,949 transcripts and 89,579 genes were obtained from the two groups. 843 DEGs showed significant differential expression among 89579 unigenes between two groups, of these, 366 DEGs were up-regulated while 477 DEGs were down-regulated. Overall design: The experiment was conducted at Ningxia Fisheries Research Institute in May 2016 using F3 S. lanzhouensis fingerlings generated by F2 selectd female parent and wild male of S. lanzhouensis, following the procedures conducted in Nile tilapia [1,2] with modifications according to growth regime of S. lanzhouensis and available equipment.The fish were reared for 16 wk prior to challenge in an experimental tank (diameter 1.2m, and depth 1.5m).Tanks were set up with a constant flow-through system (0.5 l/s) with fresh pond water at oxygen levels (8.0–10.0 ppm) and ambient temperature (～24°C). Meanwhile, according to the growth trait of S. lanzhouensis, the heaviest three fish and the lightest three fish from the tank were selected and divided into SLA and SLB. Muscle was withdrawn from the back of the fish (1.5–2.0g) for RNA extraction. Tissues were placed into RNAlater, and then moved to -80°C for storage until use.Then,RNA-Seq was carried out.