In order to investigate the influence of different primary colors on observers’ color matching accuracy and observer variability, LED-Panel with 6 channels (R₁R₂G₁G₂B₁B₂) was employed and 4 corresponding combinations with different RGB primary colors were generated. 24 observers (aged from 21 to 25) with color normal vision were organized to carry out the color matching experiment. There are 6 colors, including white and 5 CIE recommended colors were displayed on NEC-PA242 professional display as target colors, and in total, 720 sets of data were collected. CIE 1976 u'v' chromaticity values were used to analyze the color matching accuracy. The results indicated that higher accuracy was occurred in the combination of 636 nm-534 nm-452 nm,with Δ(u', v') value of 0.0062, while the accuracy was poor based on 636 nm-524 nm-472 nm, with Δ(u', v') value of 0.0084. The observer's covariance chromaticity ellipses were constructed using the inverse covariance matrix parameters of u'v' value of the observers’ matching data. The results showed that based on the combination of 636 nm-524 nm-452 nm, the average size of the ellipse was the smallest (S=0.0055) and the largest size was occurred in the combination of 636 nm-508 nm-452 nm (S=0.0094). The color matching accuracy and the observer variability were less affected by the red channel, and more affected by the peak wavelength positions of the blue and green channels.