In order to optimize the wavelength of modeling interval, iPLS method and SEV/SEC (standard error of verification/standard error of calibration) were combined to quantitatively analyze the initial boiling point of jet fuel. The results show that the performance of the correction model established by iPLS method combined with SEV/SEC combination evaluation index using the selected spectral interval is greatly improved, the coefficient of determination (R2) and standard error of verification (SEV) of the model are 0.94 and 1.05 respectively, which are 55.70% and 36.23% higher than the full spectral region model, and 44.44% and 17.50% higher than the traditional iPLS method, respectively. The feasibility and effectiveness of this method are verified by t test method.