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During recent decades, Burundi was threatened by recurrent dry events resulting in crop failure and more socio-economic losses. To assess the drought occurrence, duration and intensity, this study used the Standardized Precipitation Index (SPI) at 3-, 6- and 12-month time scales for the period 1981–2017. The Mann Kendall and Modified Mann Kendall trend tests and Sen's slope statistic test were used to analyse the spatiotemporal drought trend. The overall analysis of SPI-3, SPI-6 and SPI-12 results revealed that the northern part of Burundi was the most threatened by dry events, where more than 80% of the extremely and severely dry events occurred within the period 1993–2000. The drought magnitude highly varied during the short rains season (SOND) specifically during the 1990s decade. The cumulative frequency of extremely dry events was very high in the North with 5.2%, 6.1% and 7.4% at 3-, 6- and 12-month time scales respectively. Likewise, the northern part experienced short, medium and long dry periods, thus 88 consecutive dry months within only 8 years. The North and East regions exhibited a positive increasing trend over annual and seasonal time scales at 3, 6 and 12 months while the mountainous region and the South experienced a significant decreasing trend. Investigation of teleconnection factors showed that dry events are associated with sea surface temperature anomalies over the Indian Ocean resulting in the weakening of southeasterly winds during the negative phase of Indian Ocean Dipole and La Nina years. [ABSTRACT FROM AUTHOR]