The Serra da Mantiqueira Environmental Protection Area (SMEPA) is one of the most important and unique Brazilian conservation units of the Atlantic Forest biome, located in the eponymous relief unit. Although the environmental and water resources relevance of the SMEPA is widely known, it lacks specific studies about the hydrologic behavior of the region. This paper aims to contribute to the understanding of the rainfall behavior over the SMEPA, by detecting monotonic trends of total annual and seasonal rainfalls. The study was performed by applying the Mann-Kendall test to 37 years series from 23 rainfall stations located within and around the SMEPA. No trends were detected in total annual and spring seasonal rainfall. Few stations (one during summer, two during autumn and two during winter) presented statistically significant trends, indicating that there is no regional trend over the SMEPA region. The isolated significant trends detected suggest the existence of sites with distinct rainfall behavior in the mesoscale.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)