An economical hydrogen pero:dde bleaching warns by reducing time and temperature compared with the conventional high temperature bleaching using some activators Is the objective of this investigation. Potaaillal persulphate or ascorbic acid was used as activator In the bleaching process applied on some Egyptian cotton fibers (Giza 80, Giza 83, C123 88, and Gaza 90). Detailed laboratory esawiments were performed to Investigate the effect of the activators concentration, time required for bleaching, and temperature for the bleaching bath on the measurements of whiteness (WI), tensile strength (I gftex), and elongation at break (E%) of samples under investigation compared with the values for the same fiber samples using conventional high temperature bleaching.  The results obtained revealed that as both potassium persulphate and ascorbic add concentrations used as activators increase, the WI, T, and E% decrease. The time required to reach the maximum WI was reduced in the presence of the activators than that of the conventional bleaching method. A low temperature (30-60t) bleaching process has been established in the presence of activators. The presence of activators improved the mechanical properties of the bleached cotton samples used in this Investigation. The results obtained by statistical analysis showed that there were highly significant differences between cotton varieties for every treatment. Gin 83 showed the highest response to potassium persulphate treatment whore Giza 88 Mowed the highest response to ascorbic add treatment