The study objectives aim at describing changes in epidemiological, virological, entomological characteristics of dengue fever in South of Vietnam, period 2001-2011. The result showed that in South Vietnam, dengue has ranked 1st on mortaltity and 5th on mortality in the list of 26 notifiable infectious diseases, periode 2001-2007. South Vietnam is also the major area of dengue epidemic of the whole Vietnam. The proportion of Dengue fever in the Eastern part of South Vietnam has grown up from 20.4 percent in 2001 to 47.3 percent in 2011. Group of age 15 years maked up 26 - 32 percent of dengue cases in 2001-2003 to 35 - 41 percent in 2009-2011. In the Eastern part, dengue in age 15 group was 40 - 90 percent while in the Western part the proportion was 10 - 50 percent. Four serotypes are present in the South and dominate alternately. Main vetor for dengue transmissionis A. aegypti. It is resistant to pyrethroid groups.