Cotton fiber maturity has been reported as average maturity and maturity distribution in a sample, through measuring the fibers in the way of either an individual fiber cross-section or a longitude of several subsamples by cross-sectional image analysis (IA), advanced fiber information system (AFIS), and Cottonscope method. As a different approach, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy was proposed to estimate fiber maturity (MIR) and maturity distribution at a bundle fiber level on the basis of three MIR (low-, mid-, and high) classifications. Although maturity distributions from IA, AFIS, or Cottonscope measurement are reported, they are not related with high-volume instrument (HVI) and AFIS qualities considerably. Novelty of this study examined the effect of individual three MIR indices and additional MIR differentials on HVI and AFIS qualities in commercial cotton fibers. There were statistically significant and moderate-to-strong correlations between the MIR indices and fiber maturity and fineness measurements, and also moderate correlations between the MIR indices and other fiber qualities (for example, HVI strength). In particular, there was a moderate correlation between MIR readings and one fiber length parameter [AFIS L(n)] or two short fiber content (SFC) properties [AFIS SFC(w) and AFIS SFC(n)]. Meanwhile, MIR differential (D3) was observed to be correlated with HVI strength significantly and strongly. The result indicated the capability of ATR FT-IR spectroscopy for monitoring fiber maturity distribution in commercial cotton fibers and further in understanding fiber quality measurement.