Understanding the distribution law and influencing factors of available silicon content in Jiangxi upland soil can provide theoretical basis for adopting reasonable silicon fertilizer application measures in Jiangxi upland soilin the future. In thisstudy，citric acid extraction -silicon molybdenum blue colorimetric method was used to determine the available silicon content of 185 soil samples in the upland plough layer of Jiangxi province. The results showedthat:(1)The available silicon content in the upland soil of Jiangxi province ranges from 12.7 mg·kg -1 to 192.0 mg·kg -1，and there are significant differences in its spatial distribution. The overall distribution characteristics ofsoil available silicon content are higher in the north region and westregion，lower in the south region and the eastregion，while the lowest area locates in the northeast of Jiangxiprovince.(2)The available silicon contents in thesoils of northeastJiangxi，north Jiangxi and west Jiangxi increasesignificantly( P <0.05)with the increase of soilpH value. The content of available silicon in upland soil in southern Jiangxi decreases significantly( P <0.05)withthe increase of available nitrogen and availablephosphorus.(3)The average content of available silicon in upland soilexcept northeast Jiangxi is higher than that in paddy field in Jiangxi province.Moreover，the available silicon content in upland soil is mainly concentrated in the range of 25～ 115 mg·kg -1，while the available silicon content in paddy soil is mainly concentrated in the range of 25～ 70 mg·kg -1. The proportion of soil withdeficient(25～ 70 mg·kg -1)and extremely deficient(< 25 mg·kg -1)available silicon content in upland is 7.09% and 6.03% lower than that in paddyfield，respectively .However，the proportion of soil with deficient and extremely deficient available silicon content in upland field in Jiangxi province is 57.3% and more than half. It needs to be improved through reasonable fertilization to ensure crop yield and quality.