Introduction: Nowadays, many people have bought and installed home water treatment devices (point-of-use drinking water treatment systems), as an essential measure, to improve their health.
Materials and Methods: This cross-sectional study was conducted to evaluate the parameters of drinking water of Rafsanjan city and home water treatment device in summer 2017. Water samples at the inlet and outlet of the device with 15 day intervals for three months (approximately 48 samples, summer) were collected. Then, the concentration of heavy metals, total hardness, EC, sodium and nitrate were measured in inlet and outlet of treatment devices. All data were statistically analyzed by SPSS software version 18.  
Results: The results showed that in the inlet water, the EC and pH values were in the standard ranges. The concentrations ​​of arsenic was higher than the permissible limits and other parameters including total hardness, calcium, sodium, magnesium, nitrate, copper, zinc and lead were lower than the standard limits. The highest reduction efficiency was obtained for copper, zinc and arsenic respectively, and the lowest reduction efficiency was reported for nitrate and calcium.
Conclusion: Therefore, it can be concluded the devices could reduce the concentrations of the parameters under the standard limits. Due to the relationship between heart disease and light water, it is suggested that, in view of the high arsenic content in Rafsanjan water, filters at the inlet municipal water can be used to absorb heavy metals, especially arsenic.