The incidence rate of central nervous system (CNS) diseases is increasing annually. One of the most important obstacles encountered in the course of drug treatment for such diseases is the physiological barrier of the brain itself, the blood-brain barrier (BBB). However, the biochemical and physical methods currently used to alter BBB permeability have several side effects. Evans blue (EB) was used as a tracer to investigate the relationship between different pulse microwave parameters and changes in BBB permeability, using tissue homogenization and fluorescence observation methods. BBB permeability increased with brain field strength when the number of pulses was 20, the pulse width was 750 ns, and the brain field strength was either 10 or 12 kV/m. Notably, EB leakage was 1.8 times that of the control group, which was a statistically significant difference (p<0.01). When the brain field strength was 10 kV/m and the pulse width was 750 ns, as the number of pulses increases, the BBB permeability first increased rapidly; however, when more than 20 pulses were applied, BBB permeability reached a constant value, and EB leakage was 1.9 times that of the control group, which was statistically significant (p<0.01). Lastly, when the brain field strength was 10 kV/m and the number of pulses was 20, as the pulse width increased, BBB permeability first increased rapidly but then increased with a slower rate, at pulse widths of 750 ns and 1 000 ns, respectively. The EB leakage was 1.7 times that of the control group, with statistical significance (p<0.01). The dose-effect relationship between the pulse microwave parameters and BBB permeability changes was further obtained through data fitting. This study provides data support for medical applications and the safety protection of pulsed microwaves.