Water well drilling refers to the process of drilling into the ground to find an underground reservoir of water. This water can be potable, briny or mixed with contaminants and is used for drinking water, for watering stock or to water plants depending on its quality.

The earliest water wells were dug by hand in the form of shallow pits in areas where the underlying water table was close to the surface; often these would be reinforced with stone, masonry or wood to prevent their collapse.

Modern drilling techniques use drill shafts of regular lengths that can be connected together to reach deep water reserves and that produce narrow bore holes through which the water can be pumped as required. This process can be done manually or with specialized mechanical equipment which can be extremely sophisticated with features to precisely control water pressure through the bore hole.