Background: Many studies have showed that electromagnetic field decrease anxiety. In this study the objectives: effect of Electromagnet Fields in Low Frequency in Induced Anxiety by formalin. Methods: 32 male mice with weight (30 grams) were classified in 4 groups (n=8), and received Histamine (5mg/kg IP injection) 3classes of every group exposed to electromagnetic field (emfs) with25, 50, 75 HZ& frequency with intense250µT for10 min before injection. One group was chosen as control. Anxiety signs in 3groups (expose) compared with control group.