Selenium is an essential trace element and its levels in blood have been widely used for assessing Se status in humans. The aim of this present study is to develop a suitable method for the determination of Se in red blood cells (RBC) using ICP-MS after microwave digestion. The blood samples were obtained from patients with benign prostatic hyperplasia (BPH), who attended urology clinics at the Princess Alexandra hospital, Brisbane, Australia. No apparent polyatomic and matrix interferences were encountered when 82Se isotope was used for the analysis of Se levels in RBC. Whole Blood Seronorm Trace Elements (SERO, Norway) and dogfish muscle (DORM-1, NRCC) were used as reference materials for method validation. The method was rapid and accurate, and ideal for routine analysis of Se in RBC, and in particular for assessing of Se status in humans.