In observational studies, type 2 diabetes is associated with two- to fourfold higher risk of cardiovascular diseases (CVD). Using data from the China Kadoorie Biobank (CKB), we examined associations of genetically predicted type 2 diabetes with CVD among ∼160,000 participants to assess whether these relationships are causal. A type 2 diabetes genetic risk score (comprising 48 established risk variants) was associated with the presence of carotid plaque (odds ratio 1.17 95% CI 1.05, 1.29 per 1 unit higher log-odds of type 2 diabetes; = 6,819) and elevated risk of ischemic stroke (IS) (1.08 1.02, 1.14; = 17,097), nonlacunar IS (1.09 1.03, 1.16; = 13,924), and major coronary event (1.12 1.02, 1.23; = 5,081). There was no significant association with lacunar IS (1.03 0.91, 1.16, = 3,173) or intracerebral hemorrhage (ICH) (1.01 0.94, 1.10, = 6,973), although effect estimates were imprecise. These associations were consistent with observational associations of type 2 diabetes with CVD in CKB ( for heterogeneity >0.3) and with the associations of type 2 diabetes with IS, ICH, and coronary heart disease in two-sample Mendelian randomization analyses based on summary statistics from European population genome-wide association studies ( for heterogeneity >0.2). In conclusion, among Chinese adults, genetic predisposition to type 2 diabetes was associated with atherosclerotic CVD, consistent with a causal association.