The influence of temperature and citric acid treatments on increasing the resistance of starch's extracted from ten genotypes of corn by treatment with alpha-amylase activity was studied. The study also included the effect of these two treatments on increasing the percentage of amylose, in addition to some physiochemical behavior such as; water binding capability, swelling capacity, and solubility. The research findings revealed significant differences among the studied genotypes in response to the two treatments. In most cases, both treatments resulted in an increased in amylose content, typically within the range of 0-10%, with the acid treatment showing a more pronounced effect compared to the other treatment. The percentage of resistant starch varied significantly across the genotypes, ranging from 14.079% to 26.40%. Furthermore, the thermal and acid treatments had noticeable impacts on the physical characteristics of the starch samples. Overall, solubility and water binding values increased, while swelling values decreased due to these treatments.