A study was conducted to assess the effect of breed, sex and age on growth, haematological, serum biochemical and carcass characteristics of Turkey. The data was generated from 100 Turkeys which comprised 50 Norfolk breed and 50 Mammoth breed. The growth traits included biweekly body weight (BW) and linear body measurements: neck length (NL), body length (BL), thigh length (TL), shank length (SL), chest girth (CG) and wing length (WL). Haematological parameters included packed cell volume (PCV), haemoglobin (Hb), pH, red blood cells (RBC) and white blood cells (WBC). Biochemical parameters included total protein (Tp), aspartate transaminase (AST), alanine transaminase (ALT) and creatinine and all the carcass traits (live weight, dressed weight, carcass weight, thigh, breast, wing, back, drumstick and neck). The results obtained for body weight at 20 weeks were 4.15kg and 2.80kg, respectively for male and female Norfolk while for Mammoth were 3.70kg and 3.02kg for male and female, from the result it shows that the male of Norfolk have significantly (P<0.05) higher BW than the male of Mammoth but the female of Mammoth have significantly (P<0.05) higher BW than the female of Norfolk. For linear body measurements the result shows that the male of Norfolk have the higher values which are significantly (P<0.05) different in all the parameters measured than the Mammoth male but no significant (P>0.05) difference were observed in all the parameters measured between the females except for BL where the Mammoth female have significantly (P<0.05) higher value than that of Norfolk. The result of haematological parameters shows that there were significant (P<0.05) difference between the breeds but no significantly (P>0.05) difference between sex within breed with Mammoth having the best values in all the parameters measured except for WBC, where the Norfolk have the best values. For biochemical parameters it shows that there were significant (P<0.05) difference in Tp and ALT values between the breed but no significant (P>0.05) different between sex within breed. AST and Creatinine have no significant (P>0.05) difference between and within the breed. The result of carcass shows that there were significant (P<0.05) difference in all the traits measured between and within the breed except thigh which has no significance (P>.05) difference by the breed and sex. For the organs Norfolk also have the higher values. The result for correlations shows highly positive correlation and high significant (p<0.01) between neck and thigh with moderate between drumstick and breast and all other traits that were measured are highly positively correlated in Norfolk while in Mammoth it was moderate to low positive correlations between the traits. In conclusion the Norfolk breed is better because it has high body weight and fast growth, so the farmers should go for Norfolk.