Abstract Background: Incretins have opened a new era in type 2 diabetes mellitus (T2DM) pathogenesis. The present study aimed to assess whether there is an association between GIPR rs2302382, GIPR rs1800437 and GLP‐1R rs367543060 polymorphisms with T2DM or not and also to determine the effect of these polymorphisms on gastric inhibitory polypeptide (GIP) and glucagon‐like peptide‐1 (GLP‐1) levels. Methods: One hundred and fifty T2DM patients and 150 healthy controls were included in the study. Polymorphisms of GIPR rs1800437, GIPR rs2302382 and GLP‐1R rs367543060 were genotyped using restriction fragment length polymorphism (RFLP)‐polymerase chain reaction (PCR), multiplex allele‐specific PCR and RFLP‐PCR respectively. GIP and GLP levels were measured by an enzyme‐linked immunosorbent assay. Results: We found a significant association of both the homozygous AA and the minor allele A of GIPR rs2302382 with T2DM. The frequency of haplotype C(rs2302382) G(rs1800437) was significantly higher in controls than in diabetics; odds ratio (95% confidence interval): 1.99 (1.44–2.75) (p < 0.001), whereas the haplotype A(rs2302382) C(rs1800437) was significantly higher in patients than controls. We did not find any association of GLP‐1R rs367543060 polymorphism with T2DM. We found a significant increase in serum total GIP and a significant decrease of GLP‐1 levels in T2DM patients.