Transcription of RNA from the beta-globin (major) gene in nuclei from induced mouse erythroleukemia cells terminates within the region between 700 to 2000 bases downstream from the poly(A) addition site, but not at particularly favored sites. In addition we present the first analysis of in vivo labeled RNA from a cell transcription unit that shows RNA termination in the same region as diagnosed by analysis of in vitro labeled RNA. The region in which termination occurs is contained in 1414 bp that were sequenced beginning 600 bases downstream from the poly(A) site. There is an increased frequency of the sequence AATAAA at the beginning and a stem and loop structure followed by a string of Ts near the end of this region.