A field trail was conducted at a field near Port Said Agricultural Research Station farm, ARC, during the two successive summer seasons 2013 and 2014 to study the physiological response of rice Giza 178 cultivar grown under saline soil to potassium fertilization as soil dressing at rates of 0, 24, 36 and 48 kg K₂O/fad and spraying 2% K₂O in combination with adding 24 and 36 kg K₂O/fad. Results of combined analysis could be summarized as follows: Significant increase was recorded in plant height, leaf area index (LAI), crop growth rate (CGR), net assimilation rate (NAR), photosynthetic pigments, potassium content, panicle length, panicle weight, 1000- grain weight, grain and straw yields when plants received 36 kg K₂O /fad plus spraying 2% K₂O. Also, significant increase was recorded in proline and sodium contents, and sodium/potassium ratio in leaves when plants sprayed with water (control) as compared with other potassium treatments.