Abstract: This study was conducted to determine effect of dietary calcium supplementation on production performance and egg shell quality during the late laying period. 120 Lohman LSL white layers 70 wks of age were blocked according to the cage location and then assigned randomly to receive one of five diets added to 0, 1, 1.5, 2 and 2.5% Ca for 8 weeks. There were five diets, each diet was replicated in six times, each cage containing of four hens. Egg Production (EP) and Breakage Egg Ratio (BER) were recorded daily. Feed Intake (FI) and Egg Weight (EW) were measured biweekly. A sample of 6 eggs from each group were collected randomly every two-weeks for Specific Gravity (SG), Shape Index (SI), Shell Strength (SS) and Shell Thickness (ST). In this study, feed intake, Feed Conversion (FC), egg weight, Egg Production (EP) and specific gravity were not influenced from dietary treatments. However, breakage egg ratio, shell breaking strength and shell thickness were affected from dietary treatments by statistically significant (p<0.05). There were numerically differences among the groups in egg production, feed intake, feed conversion, egg weight, specific gravity and egg shape index but not significant by statistically (p>0.05). Egg production and feed intake decreased linearly as increasing dietary Ca levels. The highest egg production observed with hens fed the control diet. However, the highest egg weight obtained form hens fed containing highest level of Ca. Shell thickness and shell breaking strength increased whereas breakage egg ratio decreased dependent on increasing of dietary Ca levels. The highest shell thickness and shell breaking strength were established hens fed containing high level Ca whereas the lowest breakage egg ratio was obtained from same group. In conclusion, under the conditions of the current experiment, the use of supplemental Ca provided significant advantage for shell quality but not production parameters.