A fast method for batch screening diamonds includes placing diamonds on a worktable, turning on a light source arranged on one side of the worktable to shed light on the diamonds where the light includes visible light, photographing the diamonds on the worktable through an imager to obtain a basal image showing the distribution of the diamonds, switching the light source to shortwave UV light with a wavelength ranging from 180 nm to 250 nm, maintaining the light source in work condition for a period of time and then turn it off, photographing the diamonds on the worktable through the imager to obtain a phosphorescence distribution image showing phosphorescent diamonds, overlapping the basal image with the phosphorescence distribution image to obtain a phosphorescence comparison map, marking the phosphorescent diamonds on the phosphorescence comparison map through image recognition technology, and then picking out the phosphorescent diamonds as suspicious diamonds.