Pore fluid pressure generated by dehydration of hydrous minerals can trigger deep and intermediate-depth earthquakes. To investigate its effect on frictional behaviors, we conducted friction experiments on simulated bassanite gouges and observed the stress drops and recurrence intervals of stick-slip events decreased over time under 200 MPa and 110 °C. Microstructural observations indicates that gouges deformed under room temperature shows the development of numerous shear bands including Riedel shears. On the other hand, a sample deformed under 200 MPa and 110 °C had few Riedel shear planes, indicative of the elevated pore fluid pressure suppressing the development of shear planes. We derived time function of dehydration-driven pore fluid pressure evolution using Avrami kinetics. Because of the mathematical similarity of Avrami equation and the fractal geometry, our result shows that the kinetics-driven pore fluid pressure evolution controlled the stick-slip behaviors of the basanite gouges under dehydration.