The prevalence of Ascaridia galli infection has increased in free-range laying hens in Europe (Thapa et al.,2015).This is a cause of concern in Australia, where the poultry industry is rapidly moving towards free-range egg production and the impact of infection on nutrient absorption and performance is unknown. It is important to monitor the performance and egg quality of laying hens infected with A.galli to develop effective control measures in the future. Two studies were conducted to investigate performance and egg quality of laying hens either artificially or naturally infected with A. galli. Experiments were conducted each using 200 Lohmann Brown laying hens allocated to one of four treatments with five replicates of 10 hens per pen.In Experiment 1, hens allocated to Treatment 1 (Control) were routinely dewormed using levamisole (4mL per bird).