Characteristics of the spine of 'Monthong' durian such as color of the tip have been known to be an indicator of fruit maturity. Visible spectroscopy of the spine of durian was investigated for classification of maturity. Partial least squares discriminant analysis was performed to model the classification. The model using absorbance spectra transformed by the standard normal variate achieved the best accuracy of classification (94.7%) into four maturity classes ranging from 113 to 134 days after anthesis. The classification was attributable to the absorbance of chlorophyll a, carotenoids and anthocyanins in the spine. (C) 2012 Elsevier Ltd. All rights reserved.