The adiposity hormone, leptin, plays an important role in the control of glucose metabolism by its action in the brain. The effects of leptin are reducing body adiposity, food intake and improving insulin sensitivity in peripheral tissue by indirect mechanism. This study was performed to investigate the prevalence and association A19G and K109R polymorphisms in leptin (LEP) and leptin receptor genes (LEPR) with diabetes and obesity in Yazd, Iran. In this case control study, the case groups were 100 obese people with type 2 diabetes mellitus and the control groups were 100 healthy people. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The allele frequency for A and G alleles in LEP gene (A19G) were 0.275 and 0.725, respectively. Also K and R alleles in LEPR gene (K109R) were 0.36 and 0.64, respectively. The genotype and allele frequencies were not significantly different for patient and control groups. HBA1C and leptin were high in patient group. The LEP and LEPR SNPs in this study may not be useful markers for obesity or diabetes in Iranian population but with attention to the past studies these SNPs may have synergistic effects on obesity and diabetes.