The present study was carried out to investigate the effect of some different chemical egg disinfectants against bacteria and to study its effect on embryonic mortality, hatchability and some blood biochemicals parameters. A total of 525 hatching eggs (38-wk-old Golden Montazah) were randomly distributed to seven equal groups. The first group was disinfected by formaldehyde. The second, third and fourth groups were sprayed by 3, 5 and 7% Hydrogen peroxide. While, the fifth, sixth and seventh groups were sprayed by 0.1, 0.5 and 0.7% TH4 (DDAG). Total bacterial counts on hatching eggshell surface and chicks' caeca salmonella counts, embryonic mortality, hatching percentage, hatched chicks' weight, and relative weights of liver and spleen were measured. Serum total protein, albumin, globulin, glucose, uric acid, creatinine, alanine transaminase, aspartate transaminase, and triiodothyronine concentrations were determined. Results indicated that the total number of bacterial counts were significantly higher at pre-disinfection than post-disinfection. The lowest number of bacteria detected was that of the 7% of Hydrogen peroxide and 0.7% TH4 groups. Total embryonic mortality was significantly lower, while, hatchability percentage was higher in the formaldehyde group than the other disinfectants groups. Also, hatchability traits were significantly better while, embryonic mortality were significantly lower in the 5% Hydrogen peroxide group. In addition, protein profiles, glucose, and triiodothyronine concentrations were significantly lowered, while, kidney and liver functions were significantly higher in the formaldehyde group. While, its values improved in the 5% Hydrogen peroxide group. In conclusion, our results recommended using 5% Hydrogen peroxide as egg disinfectants against bacteria due to its effectiveness and ease of application