The authors reported the results of paludometric and entomological studies carried-out for two years: 1995-1996 in two localities: Ampanihy and Ankilimivory located in the South of Madagascar. These studies followed a suspect malaria epidemic in Ankilimivory in June and July 1994; the population plasmodic index was of 45%. In April 1995, this data was of 35% in Ampanihy and of 15% in Ankilimivory. Entomological studies carried out in April 1996 allowed to find Anopheles funestus in Ankilimivory and Anopheles gambiae l. s. in the two localities. Both the endemicity of malaria and the role of A. funestus had to be taken into account in the southern part of Madagascar. Until now, rare epidemics in this area were thought to occur only when climatic conditions were favorable, mainly during the rainy season. However, other factors, linked with the development could also facilitate the upset of epidemics, e.g.: irrigation programmes.