Duck is the second-largest poultry industry that provides income to farmers through egg and meat production in the Philippines. The study was designed to evaluate the egg quality of Philippine Mallard duck (Anas platyrhynchos) under the Varying Rearing System. One hundred fifty duck hen were utilized over five months experimental period under three rearing systems (confinement, semirange, and free-range system) replicated five times. A total of fifteen (15) eggs were collected and used with at least five (5) eggs per treatment every month. Data collected on egg quality are egg yolk color, egg yolk weight, egg albumen height, shell thickness, and shell weight. The general mean values on egg quality revealed a consistent significant difference (P<0.05) on treatments under outdoor rearing systems (semi-range and free-range systems) compared to confinement rearing systems. This could be attributed to the duck hen’s exposure to the grounds (soil & soil micro-organism and forages), swimming pond, and other external factors such as sunlight, rain, and air. Nonetheless, inconsistencies were observed during the monthly data analysis; hence, a follow-up study should be employed to validate the present study results.