Abstract: High-quality magnesium borate whisker was synthesized by high temperature-flux-wet method process with magnesium hydroxide and boric acid as raw materials.The synthesized samples were characterized by X-ray diffraction（XRD）， scanning electron microscopy（SEM），high resolution transmission electron microscopy（HR-TEM），and selected area electron diffraction（SAED）.Effects of calcination temperature，calcination time，amount-of-substance ratio of boron to magne-sium，and dosage of flux on whisker′s morphology were investigated systematically.Results showed that smooth-faced magnesium borate whisker with diameter of at 0.5~0.8 μm and aspect ratio of at 40~240 could be synthesized while calcination temperature was 850 ℃，calcination time was 4 h，amount-of-substance ratio of boron to magnesium was 3∶1，and dosage of flux was 4∶1.Growth mechanism of magnesium borate whisker synthesized through high temperature-flux-wet method process was also discussed.

Key words: magnesium borate whisker, high temperature-flux-wet method, magnesium hydroxide