Sr isotopes (87Sr/86Sr), Li contents and Li isotopes (δ7Li) were determined in drill core samples (sediments and rocks) and fluid (brine) samples to a depth of 250 m, obtained from Salar de Diablillos (southern Puna in north-western Argentina). For clastic sediment samples, Nd isotope compositions (143Nd/144Nd) were also determined. The Central Andes of South America hosts the largest known lithium (Li) anomalies in a restricted area, but the primary lithium sources of the salar deposits and the mobilization process of lithium are still a matter of speculation. Chemical weathering at or near the surface and leaching in hydrothermal systems of the active magmatic arc are considered as the two main mechanisms of Li extraction from the source rock. The lithium, strontium and neodimium isotope composition of typical salar deposits offer insights into the processes on how Li brine deposits in Andean evaporites are formed.