A field trail was conducted at South Port Said, Egypt, during the two successive summer seasons of 2013 and 2014 to study the physiological response of rice Giza 178 cultivar grown under saline soil conditions to decreasing the mineral nitrogen fertilizer from 145 to 72 or 107 kg N/ha with adding bio-fertilizers i.e. yeast extract, azolla, blue green alga and Rizobium rizobacter. Results indicated that plant height, leaf area index (LAI), crop growth rate (CGR), net assimilation rate (NAR), photosynthetic pigments, dehydrogenase activity (DHA), soluble sugars, antioxidant enzymes [catalase (CAT), polyphenol oxidase (PPO) and peroxidase (POD)], potassium content, panicle length, panicle weight, 1000- grain weight, grain and straw yields were increased when plants received 107 kg N/ha plus spraying yeast extract, followed by adding azolla, then blue green alga and Rizobium rizobacter without significant difference with the treatment of 145 kg N/ha. While, significant increases were recorded in proline, sodium contents, and sodium/potassium ratio in leaves when plants received 72 Kg N/ha with Rizobium rizobacter followed by blue green alga then azolla and finally yeast extract as compared with other treatments.