Strontium (Sr) is a naturally present trace element in groundwater, and its concentration can vary widely depending on geology, hydrochemistry, and climate. This study integrates the geochemical behaviour of Sr in groundwater environment, emphasizing its sources, mobility, and potential as a tracer of deep groundwater mixing. Sr usually originates from the dissolution of carbonate, sulphate, and silicate minerals, with carbonate aquifers often contributing the highest concentrations. Its mobility is governed by pH, competing ions, ionic strength, and residence time, while redox conditions exert only indirect effects through mineral solubility. Typical concentrations range from <1 mg/L in shallow fresh recharge zones to >10 mg/L in deep, mineralized, or saline systems. High Sr levels in shallow aquifers may indicate deep groundwater input, particularly when accompanied by elevated total dissolved solids or other tracers. The research highlights Sr's utility as a conservative tracer when a significant geological difference exists between shallow and deep aquifers. Understanding the concentration data requires considering local geochemical processes, co-precipitation and evaporation. When used in combination with other hydrochemical indicators, Sr concentration can present a valuable tool for identifying groundwater mixing and tracing water-rock interactions over varying spatial and temporal scales.