Abstract: A rapid NIR measurement was applied to flash point of using lubricant. The spectra band were chosen by comparing sample's spectra and mixed fuel's spectra. The different calibration models of flash point were built by the means of ANN and PLS respectively. Then these models were compared through model valid parameter. In result, the ANN model with three characteristic bands was optimal. Its R² and SEP were 0.918 3, 3.06 ℃ respectively. It was indicated that ANN method can determinate flash point of using lubricant as a non-linear chemometrics means, which could take place of traditional method for rapid measurement of diesel lubricant quality. That's to say, NIR technology was an important technology to judge using lubricant whether mixed with light oil and provide instruction for confirming equipment failure in time.