Sixty four, 30-week-old, Lohmann Brown-Lite laying hens were randomly allocated to one of four treatments with eight replicates per treatment and two hens per replicate for a 10 week study. The control diet was a high energy (11.81 MJ/kg) diet and the moderate energy (11.39 MJ/kg) diets were formulated dropping the level of animal fat. The three moderate energy diets were fed either unsupplemented (0.0%) or supplemented with 0.05 or 0.10% glycine. There were no significant differences (p>0.05) in hen-day egg production, egg weight, feed intake or feed conversion between birds fed the unsupplemented moderate energy and high energy diets. Significant differences were detected concerning egg components and quality measurements as assessed by albumen percentage (p = 0.02), yolk weight (p = 0.02), yolk percentage (p<0.01), yolk to albumen ratio (p<0.01) and yolk color (p = 0.01) between birds fed the unsupplemented moderate and high energy diets. Glycine supplementation of the moderate energy diet linearly increased (p<0.01) egg weight and feed intake with no significant (p>0.05) effects on egg production or feed conversion. Glycine supplementation significantly increased egg content (p<0.01), albumen weight (p<0.01) and percentage (p<0.01) as well as yolk weight (p<0.01) while yolk percentage (p = 0.04), yolk to albumen ratio (p = 0.01) and egg shell percentage (p<0.01) were linearly decreased. Supplementation with glycine produced a tendency (p = 0.09) towards an increase in the percentage of large eggs (63-72.9 g) produced with a concomitant decrease in the percentage of small (below 53 g) eggs (p = 0.09). The overall results of this study indicate that glycine supplementation of laying hen rations has the potential to increase egg production and weight. These increases appeared to be mediated through increases in feed intake and the ileal digestibility of fat and energy.