Reference blood chemical values were determined for 65 male and 61 female ostriches (Struthio camelus) 1 month to 72 months of age. Plasma values of glucose, total protein, triglycerides, cholesterol, uric acid, urea, bilirubin, creatinine, osmolality, electrolytes, and enzyme activity were determined. In general, differences in various values appeared mainly among age groups and less so between sexes. Older ostriches had lower plasma glucose values and enzyme activity than did younger ostriches. High plasma sodium and chloride concentrations in young ostriches correlated with high plasma osmolalities. Plasma calcium values were lower in laying ostriches. Uric acid concentrations were markedly higher than were urea concentrations in all ostriches.