In order to identify the inferior oat samples, and the samples from different local and imported brands, a nondestructive identification method based on near infrared spectroscopy and chemometrics methods was proposed. Spectra of five different brands of oat samples and inferior samples were obtained. Continuous wavelet transform was used for the baseline elimination. Wavenumber selection based on the standard deviation and relative standard deviation was discussed for improving the accuracy of the method, and 15 informative wavenumbers were obtained. Principal component analysis method was us...