A tRNA-dependent rabbit reticulocyte cell-free system has been developed which is highly active in synthesizing hemoglobin. When unfractionated tRNA is used to supplement the system, approximately equal amounts of α and β chains are produced. When tRNA fractionated by Freon reverse phase chromatography is utilized, but with a specific portion deleted, α chain production is reduced to approximately 67% of the production of β chains. © 1969.