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Precipitation is one of the most important climatic variables in the Caatinga biome that influences the spatial and temporal distribution pattern of its vegetation types. These types in turn influence the regional climate from the feedback mechanism of energy flows, water and momentum. This climate-vegetation interaction in the Caatinga is differentiated depending on the type of climate pattern in the region. This study aims to find out how the annual precipitation pattern influence the vegetation seasonality by the identification of the main phenological features of the vegetation annual growth cycles and the annual rainfall features in a gradient of five climatic regions in the Caatinga biome. We use time series (2001-2008) of vegetation indices such as NDVI and LSWI, and precipitation that was derived of TRMM satellite data and surface station data. The results indicate that precipitation variability in the rainy season influences directly the variability of vegetation growing cycles. That influence is not linear, but adjusted to a logarithmic function being precipitation better fit with LSWI (r2 = 0.67) than NDVI (r2 = 0.54). The influence of precipitation on Caatinga vegetation, using phenological metrics such as start, end, peak and length of the vegetation growing cycles, showed greater lag in climatic regions with higher precipitation while in regions with lower precipitation this lag was slight.