To test performances of different color matching functions (CMFs), we make 20 pairs of nearly metameric color patches based on 5 target colors (gray, brown, b-green, blue, and purple). The visual data from 56 observers is adopted to calculate the standardized residual sum of square and correlation coefficient. The behaviors of different CMFs from the young and old observers have large discrepancies. For young observers, S2 and S6 outperform others and CIE1931 has the worst performance. While, for old observers, CIE1931 outperforms others and CIE1964 has the worst performance. Visual data from observers under the D65 light source is used to optimize CIE1964 CMFs. After optimizing, performances for different age group improves not only for D65 light source, but also for light emitting diode source.