To explore spectral characteristics of soil organic matter (SOM) and their effects and hence to lay down theoretical basis for quantitative reversion of organic matter and soil iron oxides, effects of soil organic matter on soil reflection rate, soil line parameters and quantitative inversion of soil iron oxides were studied in this paper by making use of spectral data of the soil before and after organic matter was removed. Results show that removal of organic matter significantly raised soil reflection rate and the change was the most obvious in the visible orange light band of 570~630 nm. And correlation analysis also shows that the correlation coefficient of removal of soil organic matter with the relative variation or difference in the orange light band was higher than that in the other light bands. The highest correlation coefficient was found at 600 nm. It is, therefore, suggested that the spectral data in light band of 570~630 nm be used for inversion of soil organic matter. Removal of SOM also lowered soil line slope and significantly increased intercept. The changes in thse two aspects were significantly related to SOM remval rate. Hence, soil line parameters can be used to predict content of SOM. The effect of SOM on quantitative inversion of soil iron oxides was significant, especially in soils with SOM content being above 2%. So in performing the inversion, it is essential to take into account effect of SOM on accuracy of the inversion and adopt some effective technologies to mitigate these effects. Only by so doing, can quantitative inversion of soil iron oxide content achieve better results.