Arsenic (As) is a natural occurring element which poses a potential risk to groundwater quality, as well as food safety through As transportation in soil-water-plant systems. The present study investigated the level of As contamination in water, soil, and pistachio plants (leaves and seeds) in 7 regions of Kerman province, as one of the most important pistachio cultivation regions in Iran. The results revealed that the concentration in the soil of the sampled areas varied from 15 to 1200 mg/kg The highest As concentrations was observed in the Shahr-e Babak, Bayaz, and Sirjan regions. The As concentration in the water of the sampled areas was between 0.62 and 483 µg/L, and the regions of Sirjan and Shahr-e Babak had the highest levels of arsenic contamination. The highest accumulation of As in pistachio leaves and seeds was observed in the Shahr-e Babak, Bayaz, and Sirjan areas, which had a positive correlation with the As concentration in the soil and water of the area. Thus, the level of As in fresh pistachios in Shahr-e Babak, Sirjan, and Bayaz regions can be considered a threat to the safety of the Iranian population.