We examined the possible association between road traffic noise in residential areas and myocardial infarction (MI) incidence. We conducted an ecological study among 25-64-year-old men in the general population of Kaunas city. The study comprised all first time MI cases among stable residents of Kaunas treated in hospitals in 1999-2001 (518). We measured traffic-related noise levels at the 117 electoral districts and linked these levels to residential addresses using Geographical Information System (GIS) techniques. In daytime period (10-12 hr, 10 min.) traffic-related noise emission fluctuated between 58 dB(A) to 82 dB(A) and about 18% of citizens were exposed to noise level exceeding 65 dB(A) in their residential district. The age-adjusted MI incidence per 1,000 increased by increasing noise exposure. In the total group of 25-64 years old men the incidence tended to increase from 2.07 in the 1st (lowest) exposure area to 2.57 in the 4th (highest) exposure area (Risk ratio (RR) 1.33; 95% confidence interval (CI) 0.76-2.32). In the subgroup of 55-64 years old men, the risk ratio increased by 92% (RR = 1.92; 95% CI 1.00-3.67). Our results indicate a relationship between traffic noise exposure and MI incidence among 55-64-year-old men.