A rapid component detection method of modified Composition B was studied by near infrared spectrum technology. The quantitative models of main components TNT and RDX were established by partial least squares（PLS）method. Results show that the coefficients of determination of cross-validation （R²）of established models are 0.9611, 0.9415, respectively. The root mean square errors of cross-validation (RMSECV) are 0.478%, 0.501%, respectively, and the root mean square errors of prediction (RMSEP) of external-validation are 555%, 521%, respectively, showing that the established quantitative model has high accuracy and precision. The calculated results of t-test performed by determined values of near infrared method and reference values of the standard analysis method are t_RDX=1.03, t_TNT=0.72, respectively. Their t values are smaller than the critical value t₉=2.26 (α₉=0.05), revealing that there is no significant difference between the near infrared spectroscopy and the standard analysis method.