Two field experiments were conducted during 2016/2017 and 2017/2018 winter seasons soil at the Experimental Farm of City of Scientific Researches and Technological Applications in Borg Al-Arab, Alexandria, Egypt. The experiments were conducted to evaluate the effect of supplementary irrigation and planting distance on Quinoa (Chenopodium quinoa Willd.) cv. Nat oil yield, yield components, seed quality and water use efficiency using saline water in the arid land. The experiment design was split-plot with three replications at two seasons. Main plots were assigned to supplementary irrigation and the sub-plots were occupied by the plant distance. Under groundwater with E.C 8.3 ds/m was used for irrigation. The results revealed that there was a significant difference among the supplementary irrigation where the application of three supplementary irrigation in addition to rainfall at the first season and the application of whatever two or three supplementary irrigation in addition to rainfall grain yield and its components. Concerning the plant distance, the results illustrated that the best treatment is planting with 15 cm distance