The involvement of meteoric water in orogens dynamics through surface processes is well known as for example in the Himalayas where erosion, resulting of the interplay between climate and tectonics shapes the most spectacular landscapes on the planet. But what about more internal and deepest surface fluid infiltration? Here we report analysis of the δ18O(water)and δD(water)of extracted water from fluid inclusions hosted into Cenozoic quartz veins sampled in the core of the Himalayan range, near the Main Central Thrust and the South Tibetan Detachment. Isotopic and microthermometric values suggest a meteoric origin for the fluids trapped in the quartz of syn-to post-kinematic veins formed between 10 to 20 km depth. Moreover, the isotopic compositions obtained in this study on quartz fluid inclusions water collected along a transect across the Himalayan range evolved with the topography in a similar manner than the modern meteoric water. Considering the age of formation of the quartz veins between 18 and 12 Ma, we deduce that the morphology of the Himalayan topographic front was already shaped during the Miocene but located further north.