In this paper, two psychophysical experiments were conducted to explore the effect of peak luminance on the perceptual color gamut volume. The two experiments were designed with two different image data rendering methods: clipping the peak luminance and scaling the image luminance to display's peak luminance capability. The perceptual color gamut volume showed a close linear relationship to the log scale of peak luminance. The results were found not consistent with the computational 3D color appearance gamut volume from previous work. The difference was suspected to be caused by the different perspectives between the computational 3D color appearance gamut volume and the experimental color gamut volume/perceptual color gamut volume.