Plague remains a major public health problem in Madagascar. Faced with reports of plague cases and deaths in Tsiroanomandidy district, we performed an investigation in October 2014.Our aim was to describe the plague outbreak and to improve the national plague control strategies. We used the National plague control program case definition. We identified cases from outpatient registers and collected socio-demographic and clinical information. Plague circulation was determined through a retrospective environmental survey of rodents and vectors.