The factors significantly related to the late diagnosis of congenital heart diseases with multivariable regression analysis were acyanotic congenital heart diseases (aOR = 1.6, CI 95%: 1.02 - 2.51), the family's income under average income (aOR=2.27, CI 95%: 1.43 - 3.59), residing outside Ho Chi Minh city (aOR= 7.17, CI 95%: 2.97 - 17.34), mothers' educational level under high school degree (aOR= 2.57, CI 95%: 1.47 - 4.49), housewife (aOR= 2.02, CI 95%: 1.28 - 3.18), mothers' age < 35 years old (aOR= 3.1, CI 95%: 1.7 - 5.67), antenatal care at health commune stations, district hospitals (aOR= 5.03, CI 95%: 1.59 - 16.18), and place of newborn delivery at health commune stations, district hospitals (aOR= 3.19, CI 95%: 1.16 - 8.76) (p< 0, 05).