The identification of seed aging has a great significance for agricultural production and food security. In this paper, three kinds of legume seeds with different storage years are distinguished by a tri-step IR spectra method, including Fourier transform infrared (FT-IR) spectroscopy, second derivative infrared (SD-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy. The results show that the FT-IR spectra of three kinds of legume seeds are very similar, which are composed of the absorption peaks of protein and carbohydrate. But slight differences of original infrared spectrum of legume seeds with different storage years are observed in the range of 1800-700 cm -1. The absorption intensity ratios of three kinds of legume seeds show a decrease tendency with the increase of storage time. The variance analysis of the absorption intensity ratio show that the absorbance ratio of the seeds with different storage years is significantly different. More obvious differences are exhibited in their SD-IR spectra in the range of 1800-700 cm -1. In 2D-IR spectra, the positions, numbers and intensities of auto-peaks and cross-peaks are obvious different in the range of 860-1690 cm -1 for broad bean seeds and red kidney bean seeds, and in the range of 1350-1800 cm -1 for soybean seeds. The numbers decrease with the increase of storage years and the intensities weaken with the increase of storage years. Partial least squares analysis can accurately distinguish legume seeds with different storage years. Three kinds of legume seeds show obvious spectra differences, which demonstrate that FT-IR spectrum combined with SD-IR spectrum and 2D-IR spectrum can be used to discriminate legume seeds with different storage years. The method can provide a simple and rapid spectral method for detecting seed aging.