The importance of water in everyday life is clear for humans and living creatures. In addition to supplying the water required for the body, it also contains necessary minerals. An increase or decrease in these minerals is responsible for various diseases and problems. Due to the growing consumption of treated water in Birjand, Iran and the need for the continuous monitoring of the quality of treated water, this descriptive research aimed to determine the chemical and microbiological quality of treated water of desalination stations in Birjand from September 23rd, 2015 to March 19th, 2016 (autumn and winter). Samples were directly taken from the desalination stations of Birjand. Physical and chemical tests were performed according to the Standard Methods. The results were compared with national standards as well as World Health Organization (WHO) guidelines. The results showed that almost all measured chemical and bacterial characteristics were less than the national and international standards. Also, the samples were standard in terms of coliforms and fecal coliforms. In some stations the concentrations of free residual chlorine and also magnesium were higher than standards. Therefore, periodic investigation of quality parameters is recommended in all desalination stations to reflect the results to authorities.