There were no difference m response to cage location and T, M and B tier levels. The effects of cage location, tier level and cage location by tier level interaction on egg quality trairs such as egg weight, shell strenght, shell thickness, shell weight, yolk index, albumen index and Haugh unit were not significant in present study. A negative colTelation between light intensity and eggshell thickness is reported (Abclelkarim and Biellier, 1982). However, eggshell quality was reported as independent of light intensity or cage location and tier level in other studies including hens (Leeson and Lewis, 2004). Pavlovski and Masic (1992) housed laying hens in individual cages as 3-tier with rows facing or not facing windows and reported no differences in shell weight. As albumen index value increased, Haught unit also Increased. Albumen structure is one of the mam characteristics for intemal quality and is used for Haugh unit's calculation (Eisen et al., 1962).