The cross-sectional study of epidemiological screening type has permitted to evaluate some cardiovascular risk factors in two groups of monozygotic (MZ) and dizygotic (DZ) twins born between 1975-1990, in the town of Iaşi. In the 89 MZ pairs and 112 DZ pairs, certain constitutional and behavioural cardiovascular risk factors have presented values of prevalence with statistical signification (p < 0.05) in terms of their age, sex, the urbanisation time and the educational level of their parents. In risk factors existence or absence to both of the twins have put into evidence, to the MZ, most enhanced values of concordance as regards: overweight (66.6%), excessive consumption of salt (56.9%), food with atherogenic risk (50.9%). The concordance values have been less in DZ compared to MZ concerning all the risk factors excepting compartmental type A (77.7%). By analysing the concordance variants, an preponderant influence of the environment has been noted in the studied MZ and heredity and environment influence in DZ. By measuring the arterial blood pressure values at the twins and the twins parents, a prevalence of the essential arterial hypertension is noticed to both of the twins, 6.2% in MZ pairs and 6.9% in DZ ones.