This study investigated the effect of injection of glucose and magnesium oxide nanoparticles (MgONPs) on performance (weight gain and feed conversion ratio) and biochemical parameters (superoxide dismutase -SOD, malondialdehyde -MDA, alkaline phosphatase -ALP, transaminases -alanine transaminase and aspartate aminotransferase) and catalase -CAT in broiler chicks. A total of 105 day-old broiler chicks were randomly distributed into seven treatments (T1 -T7) with three replicates of five birds per replicate. Each treatment group was subcutaneously injected at day old with the following: T1 (without injection -control group), T2 (0.5 mL deionized water -sham group), T3 (100 mg of glucose dissolved in 0.5 mL of deionized water), T4 (100 mg of glucose and 4 mg of magnesium sulphate each dissolved in 0.5 mL of deionized water), T5 (100 mg glucose and 4 mL magnesium oxide nanoparticles solution each dissolved in 0.5 mL of deionized water), T6 (4 mg of magnesium sulphate only dissolved in 0.5 mL of deionized water) and T7 (4 mL of magnesium oxide nanoparticles solution only in 0.5 mL of deionized water). The results of this study showed that in vivo administration of magnesium oxide nanoparticles (at day old) favoured the eventual feed conversion ratio and final weight gain (1.82, 40.10 g, respectively) of the broiler birds when compared with similar values for birds without the nanoparticle injection (2.37, 33.32 g, respectively). It equally revealed that administration of the nanoparticles singly or in addition to glucose posed no detrimental effect (p>0.05) on the tissue enzymes activities of the birds when compared with the control values. Administration and dosage of the nanoparticles have to be keenly monitored in order not to have a detrimental effect on the antioxidant enzymes parameters.