Bamboo filaments were treated with boric acid and borax (the mass ratio of 1:1,
the concentration of 20%) with four different treatment methods including atmospheric immersion, cold and hot bath immersion, vacuum impregnation and vacuum-pressure impregnation. The different treatment methods on the boron loading were analyzed and
the corresponding flame resistance of bamboo filaments were evaluated by the cone analysis. The results showed that suitable treatment method with optimized processing indexes, such as hot and cold bath immersion in the condition of 100°C/2 h and 20°C/2 h with 3 cycles, was more credible to accelerate the percentages of boron loading in the bamboo filaments, and the lowest result was found in the samples with vacuum impregnation. Compared to the untreated samples, the heat and smoke release would be decreased significantly, especially for the samples with the promising hot and cold treatment, and promising pressure treatment, attributed to the more stable boron fixed in the bamboo filaments.