In this paper, three oxidation processes were employed in kenaf degumming. The properties of degummed fibers such as fineness, residual lignin content were tested, and the degumming effects were analyzed by XRD and IR spectroscopy. The crystallinity of kenaf fiber increased after being treated. The addition of the strong oxidizing agents including potassium peroxymonosulfate and peracetic acid (plan CT2) in the later process of caustic soda and hydrogen peroxide scouring (plan CT1), as well as the usage of the sulfate method after above treatments (plan CT3), resulted in the gradual increase of relative integral area value Ai/As calculated by the characteristic peaks of the cellulose in IR spectra and the gradual decrease in the sum of those of lignin and hemicellulose. At the same time, the content of lignin gradually decreased, while the fineness gradually increased. The results indicated that the three oxidation treatments adopted in degumming had obvious effects. As a new oxidant, the mixed liquid of potassium peroxymonosulfate and peracetic acid was effective on delignification.