This experiment was conducted to evaluate the influence of Spirulina platensis on growth performance, egg quality and some serum parameters of laying Japanese quails. For this experiment, 100 ten weeks-old, female Japanese quails (Coturnix coturnix Japonica) with similar body weight were caged individually and were randomly divided into four groups of 25 quails each. Quails were fed diets supplemented with 0 (control), 0.5, 1.0 and 2.0% Spirulina platensis for 8 weeks. Spirulina platensis addition did not affect feed conversion ratio, feed intake, egg production, egg weight, shape index, eggshell thickness and haugh unit, significantly (P>0.05). However, there were significant differences (P<0.05) in final body weight, yolk index, albumen index and eggshell weight of experimental groups. There were significant differences (P<0.05) between groups in low density lipoprotein (LDL cholesterol) and high density lipoprotein (HDL cholesterol) concentrations. The LDL cholesterol concentration decreased while HDL cholesterol concentration increased with the increased supplementation of Spirulina platensis. Spirulina platensis supplementation also decreased plasma total cholesterol and trigyliceride levels between groups numerically but not statistically (P>0.05). The mean egg yolk cholesterol levels dropped by 19.65 and 18.93% in the 1.0 or 2.0% Spirulina platensis supplemented groups compared with control group. In conclusion, Spirulina algae can be used safely in laying quails diets with important effects on serum parameters and egg yolk cholesterol.