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Introduction: With the increase in mobile phone usage in public places, the use of mobile phone jammer has also increased therefore, the aim of this study was to evaluate the effects of mobile phone jammer on the level of anxiety in mice. Methods: Forty male and 40 female naive mice (25-30 g) were randomly divided into four groups (control, 900 MHz, 1800 MHz and 900+1800 MHz exposures). Animals were exposed to mobile phone jammer radiation for 2 h. Then, anxiety-like behaviors were tested in the elevated plus-maze (EPM) model and light and dark (L/D) box. Results: Results showed that mobile phone jammer exposure at 900 MHz reduced the time spent in the lit side of the L/D box (P = 0.008) in male mice compared with the control group. While, 1800 MHz waves increased time spent in the lit side of the L/D box and in the EPM open arm as compared to the control group in both male and female mice (P = 0.05). Also, 1800 + 900 waves increased the time spent in the dark side of the L/D box in the female mice (P = 0.0001). Conclusion: The results showed that mobile phone jammer radiation at 900 MHz and 900+1800 MHz frequencies increased the level of anxiety in male and female mice, respectively. Thus, it seems that this apparatus cannot be used as a safe device in popular places.