The study was conducted to evaluate the effect of formic acid and/or Saccharomyces cerevisiae on breast meat characteristics of the Indonesian indigenous crossbred chickens. A total of 200 day-old chicks were randomly distributed to four experimental groups (with five replications each), including T0 (chicks fed control diet), T1 (chicks fed diet supplemented with formic acid at 2g/kg), T2 (diet supplemented with S. cerevisiae at 3g/kg) and T3 (diet supplemented with formic acid at 2g/kg and S. cerevisiae at 3g/kg). At week 9, the chicks were slaughtered and from which the samples of breast meat were collected. Our results showed that total protein was higher (p < 0.05) in breast meat of T3 than that in other groups. The moisture content and water holding capacity were lower (p < 0.05) than that in other groups. The breast meat from T0 showed higher (p < 0.05) L* (lightness) values than other meats. The fat content, pH, a* (redness) and b* (yellowness) values of meats were not substantially affected by the treatments. In conclusion, dietary supplementation of a combined mixture of formic acid and Saccharomyces cerevisiae was effective in improving the breast meat quality of the Indonesian indigenous crossbred chickens.