The experiments were conducted to evaluate the effect of soil injection treatments on yield, quality and chemical composion of potato plant (Spunta cultivar), during the seasons of 2020 and 2021. The experiments were conducted at Baloza Research Station, Desert Research Center, North Sinai Governorate, Egypt. The experimental design was a randomized complete block design with three replicates, every replicate included 4 treatments (5,10 ,15 and 20 tons) of clay. The results showed that the different clay quantities (5, 10, 15 and 20 tons/feddan) effected on the potato yield parameters with significant differences between the treatments. The highest values of number of tubers/plant, average weight of tuber, tuber weight/plant and total yield/feddan of potato plant were obtained by using 20 tons of clay quantity/feddan treatment, followed by 15 tons of clay/feddan treatment and then 10 tons of clay/feddan treatment, It is clear that the highest values of average tuber dry weight, average tuber size, average tuber length and average tuber diameter of potato tubers were obtained by using 20 tons of clay quantity/feddan, followed by 15 tons of clay/feddan 
treatments and then 10 tons of clay/feddan treatment, The highest values of carbohydrate % in tuber and tuber content of TSS of potato plant were recorded by using 5 tons of clay quantity/feddan treatment, followed by 10 tons of clay/feddan treatment and then 15 tons of clay/feddan treatment.