The Vis-NIR spectroscopy technology was studied on nondestructive measurement of sugar content in navel orange. Three different spectral ranges of 450-1000nm,1000-1800nm and 450-1800nm were selected, respectively and five different spectral pre-processing methods of Standard Normal Variate (SNV), first derivative (FD), second derivative (SD), multiplicative scatter correction (MSC) and smoothing were used for establishing the partial least squares(PLS)models, which was determined the sugar content in navel orange. The results showed that the model developed from 450-1800nm spectroscopy after SNV pre-processing achieved the optimal performance. The correlation coefficient (r2) of the calibration set and validation set were 0.9349 and 0.8514 respectively, and the root mean squared error of calibration and validation sets were 0.8017 and 1.1649, respectively. The research indicated that the Vis-NIR spectroscopy technique was feasible to nondestructive measurement of sugar content in navel orange.