In order to investigate the dependence of lightness, chroma, and hue visual tolerances upon hue angles in CIELAB color space, five hue circles were selected at different lightness and chroma levels (L*=30, 50, 70 and C*ab=10, 20, 30), which were observed using three visual scales (ΔV=3.02, 5.92和8.87 CIELAB units). The test stimuli were presented on the CRT, and the corresponding lightness, chroma, and hue tolerances were measured by a panel of 8 color-normal observers by using the psychophysical method of constant stimuli. Based on the obtained correlation between visual tolerances and hue angles, the prediction performances of the six CIELAB-based color-difference formulae, CIELAB, CMC, BFD, CIE94, LCD, and CIEDE2000, were further evaluated. The detailed analysis indicated that due to the independence between the lightness tolerances and the hue angles, all the formulae performs well, with CIEDE2000 a little better than the others. For chroma tolerances, LCD performs the best, while CIEDE2000 and BFD the poorest, and the others performs nearly the same. The hue weighting functions of CIEDE2000 and LCD outperforms others obviously, with CMC performing poorest.