Objective To explore the possible association of single nucleotide polymorphism (SNP) rs3738435 of muscarinic acetylcholine receptor subtype M3 gene (cholinergic receptor, muscarinic 3, CHRM3) with risk of type 2 diabetes mellitus (DM) and metabolic disturbance. Methods The genotypes of T-149C variant of CHRM3 gene were determined by PCR-RFLP in 573 Chinese individuals in Shanghai, including 220 newly-diagnosed type 2 DM patients without taking any drug and 353 subjects with normal glucose tolerance (NGT). In the subjects, height and weight were measured for body mass index(BMI), waist, hip and femoral circumstances for waist-to-hip ratio (WHR) and waist-to-femur ratio (WFR), and serum lipid level including total cholesterol, triglyceride, high-density and low-density lipoprotein cholesterol, blood pressure, plasma glucose levels both at 0 and 120 minute during oral 75 g glucose tolerance test (OGTT) were also determined. Results (1) There was no statistical difference in the gene frequency between groups of type 2 DM and NGT. (2) In the group of type 2 DM, significant differences were observed between TT genotype carriers and TC+CC genotypes carriers for BMI, with an obvious increase in TY genotype carriers [(26.99±3.59vs25.34±3.48)kg/m2, P=0.001]. (3) In the subgroup of type 2 DM with BMI≥25 kg/m2, total cholesterol was higher in TT genotypes than in TC+CC genotypes[(5.75±1.26vs5.27±1.14)mmol/L, P=0.030], so was the low-density lipoprotein cholesterol. Conclusion The genetic variation T-149C in the CHRM3 gene seems to attribute to weight regulation and lipid metabolism of patients with type 2 diabetes mellitus in Chinese population.