In this work, we investigated the influence of retrograde-well implantation on hetero-structure body-tied germanium (Ge) FinFET . Using structural engineering, the retrograde well was fabricated prior to Ge epitaxy, which could avoid the activated temperature of dopant in Si substrate. With optimizing the implant condition, the p-Ge/n-Si hetero-structure junction exhibited high ION/IOFF ratio and lower junction leakage (4 × 10-3 μA/cm2). Furthermore, we also make a comparison of planar and mesa junction structures, mesa junction exhibited lower junction leakage (6× 10-6 μA/cm2) as compared with the planar one mentioned before, which could be attributed to improvement in peripheral leakage due to dislocation within Ge and Si. Comparing the difference between retrograde-well and implant-free Ge FinFETs, the drain induced barrier lowering (DIBL) was considerably improved by 50 %. Our retrograde-well Ge FinFET exhibited a high ION/IOFF ratio ∼ 8×103 (IS) than the conventional Ge FinFET (ION/IOFF ∼2×103).