Abstract: Bananas are one of the most popular fruits in the world. The main producing areas can be distributed in China, Indonesia, Brazil, Ecuador, and the Philippines. Among them, the total annual banana production in China is about 13 million tons. After the banana fruits are picked, the banana pseudostems usually remained on the farm to rot or burn, leading to serious environmental pollution. The banana fiber has great potential in the textile industry, construction, automobile, and machinery fields, due to the high tensile strength and modulus, low density, and excellent antibacterial and biodegradable properties of banana fiber. Banana stem fiber can contain a large number of colloid components, such as pectin, hemicellulose, and lignin, thus limiting the application of its fiber. Therefore, it is very necessary to remove the colloid from the banana stem fiber, in order to meet the requirements of downstream. In this study, the ethylene glycol and sodium hydroxide were individually selected to degum the banana fiber at high temperatures. Firstly, the fiber was pretreated and then degummed in ethylene glycol or alkali solution at a high temperature. The degummed banana fiber was characterized by a scanning electron microscope (SEM), Fourier transformation infrared spectrometer (FTIR), X-ray diffractometer (XRD), and thermal gravimetric analyzer (TGA). The structures and composition of banana fiber were obtained under different degumming. The physical and mechanical properties of banana fiber were tested and analyzed as well. A more efficient, low-consumption batch preparation degumming was optimized, according to the amount of chemicals, processing time, and fiber properties. The results show that the residual glue rate of high-temperature alkali degumming fiber was 3.4%, which was lower than the 8.93% of the traditional alkali and the 13.13% of the organic solvent degumming. Furthermore, the cellulose content increased after degumming, with the organic solvent and the traditional alkali increasing to 68.31% and 79.27%, respectively. But both were lower than the cellulose content of 87.32% after high-temperature alkali treatment. The fiber strength of the traditional alkali treatment was 3.53 cN/dtex, which was lower than that of the organic solvent and the high-temperature alkali. This was because the fiber was over-degummed under the action of high concentration alkali solution for a long time, leading to the depolymerization and damage of cellulose, which reduced the fiber strength. The fiber strength values of the ethylene glycol degumming and high-temperature alkali were 4.72 and 4.43 cN/dtex, respectively, indicating the better holding of the fiber strength during treatment. There was a generally large diameter of ethylene glycol degummed fibers. The number of fibers above 50 μm was accounted for as high as 74%. Therefore, the ethylene glycol shared the low degumming effect on the banana fibers, where the fibers failed to separate. Compared with the traditional alkali, the number of fibers within 50 μm accounted for 57%, which was better than that of ethylene glycol degummed fibers. However, the fiber diameter was still relatively high. The normal distribution was observed in the fiber diameter of high-temperature alkali degumming. The number of fibers within 50 μm was accounted for 83%, which was the largest proportion. The fiber diameter was reduced overall, indicating that high-temperature alkali degumming effectively reduced the fiber diameter for the high quality of textile fibers during spinning. In the case of the same 500g raw hemp degumming, at least 1.96 kg of chemical reagents were required in the high-temperature alkali to prepare banana fiber. Compared with the traditional alkali and the organic solvent degumming, the amount of chemicals used in the high-temperature alkali to treat the fiber was reduced by 46.6% and 81.3%, respectively, indicating the time less than 1.75 h. The high-temperature alkali degumming can be expected for the high efficiency and low consumption suitable for banana fiber batch preparation.