Objective: To investigate the effects of electromagnetic fields on some hematological parameters of Male white mice. Methods: In this study two experiments were used as short-term and long-term experiments. Short-term experiments were carried out in 80 male white Balb/c mice exposed to two types of mobile phone for a period time up to 60 min a day for 2 weeks. Long-term experiments were carried out in 30 male white Balb/c mice exposed to two types of mobile phone for a period time up to 90 min a day for a month, two months, three months. Result: The present result found that a decline in hemoglobin, hematocrit, red blood cells count, in addition to the platelets count after short and long exposure to both types of mobile phone (Alcatel, Nokia). It was observed that the average number of white cells and lymphocytes increased significantly, indicating the increase to the body's immune response to radiation. Also, when exposed to both devices (Alcatel, Nokia) for 15 minutes, the red blood cells began to take a role of formation due to an increase in the viscosity of the blood and the ability of the cells adhesion. Increased duration of exposure to 30-minute to both devices revealed disparities in the sizes of red blood cells with the appearance of a large proportion of cells with pale colors due to lack of hemoglobin. In the group exposed for 45 minutes showed clearly the influence of mobile phones on examining blood smears which observed a proportion variation in the cell sizes with the emergence of forms of abnormal forms, including pellets cleft with many areas empty of red blood cells, With increasing in of exposure duration to 60 minutes, red blood cells appeared completely different from the natural form and took the forms resembling the eye and tear that appear in the case of anemia. After three months of exposure to both types of mobile phone showed pathological changes in red blood cells where gripped the outer membrane of the red corpuscle changes and become serrated. Conclusion: Exposure to electromagnetic fields is responsible for the variations of some hematological parameters in rats.