Abstract: In this study, the recharge processes of the springs in the Sandikli and Suhut basins were investigated by stable isotopes, oxygen-18 (δ18O), deuterium (δ2H or δD) and tritium (3H) analysis. The study area consists of volcanics, limestones and clastic rocks. There is a large number of water sources discharged from volcanic origin rocks and clastic limestones in this region. The dominant ions in the springs in the region are Ca2+, Mg2+ and (Formula presented.). The δ18O and δ2H values of the spring waters ranged between –8.0 and –10.8, –53.0 and –69.6 in September-2017, between –7.9 and –10.8, –512.0 and –69.6 in April-2018 respectively. The positions of samples on the δ18O–δ2H diagrams indicate the meteoric origin. The maximum tritium contents of the water samples 5.4 TU in September-2017 and 5.2 TU in April-2018. Deuterium excess (d-excess) values of spring waters were between 9.1 and 17.3‰ in September-2017, between 8.4 and 18.0‰ in April-2018.