This study aimed to determine the effect of concentrations of instant bread yeast and carrageenan on the quality of sorghum flour-substituted white bread. The study was an experimental method carried out in the laboratory and designed using two-factor Completely Randomized Design (CRD), namely yeast concentrations 2%, 4%, and 6% and Carrageenan 0%, 0.2%. Observational data were analyzed using analysis of variance with a level of 5% using Cos-Stat. Significantly different data were further tested by Honest Significant Difference (BSD) at the 5% level. Parameters observed included chemical quality (fiber content, ash content, and content), physical quality (swelling power, elasticity, and bread crumbs), and organoleptic quality (aroma, taste, texture, crust color, and crumb color). The results showed that yeast formulation with at 4% and carrageenan 0.2% was the best treatment in producing white bread with a moisture content of 23.72% (according to SNI), ash content of 1.9%, crude fiber content of 5.33%, 67.83% swelling power by reducing the size of the pores so as to create uniform bread pores, 84.44% elasticity with organoleptic crust color "light brown", aroma "slightly sour", taste "not sour", texture "a bit soft" and the crumb color "yellowish white" which was liked by the panelists.