It is in vitro study to examine the effect of electromagnetic radiation from router on human blood samples rheological factors, such as mean red blood cell volume (MCV) and erythrocyte sedimentation rate (ESR). Samples were irradiated for one, ten, twenty four hour, and three with 500 milli-watt. The measurements were done directly after the irradiation, chemilumenscence (CL) signal. MCV and ESR decresed after irradiation for ten hours by 20.6%, 0.41%and 5.3% respectively. This because the effect of radiation on the composition of the plasma that finally effect in ESR of whole blood.