This work aimed to study the effect of using vitamin C and alternation of drinking saline well water with tap water on hematological parameters, biochemical blood constituents, hormonal profile and productive performance of laying hens drinking saline well water under South Sinai conditions. A total number of 120 Commercial Browne Lohmann LSL laying hens (34 weeks old and average body weight of 1996.9±18.7 g) were randomly divided into four equal treatments (30 hens of each). The 1^st treatment (Tr1), hens drank tap water (containing 265 ppm TDS) and fed basal diet (considered as control). The 2^nd treatment (Tr2), hens drank saline well water (containing 3398 ppm TDS) and fed basal diet. The 3^rd treatment (Tr3), hens drank saline well water and fed diet containing 2 % vitamin C (commercial product containing 20 % vitamin C). The 4^th treatment (Tr4), hens drank saline well water alternate weekly with drank fresh tap water until the end of experiment (hens drank saline well water every other week) and fed basal diet. The results showed that red blood cells and hemoglobin level were significantly decreased, while, mean corpuscular volume and Heterophils/Lymphocytes ratio were significantly increased in Tr2 when compared with Tr1. Glucose level significantly decreased in Tr2 compared with other treatments. Cholesterol level significantly decreased in Tr3 when compared with Tr2, Tri-iodothyronine hormone significantly decreases in the Tr2 when compared with Tr3 group. Progesterone level significantly increased in Tr4 when compared with Tr2. However, there are significant differences among treatments in final body weight, egg weight, egg number, egg mass, feed conversion ratio and mortality rate. In conclusion, laying hens alternated drank saline water with tap water every week or using vitamin C in feeds may alleviate the drastic effect of drinking saline well water on blood parameters and thus positively reflected on laying hen's performance.