The high-density ammonium polyvanadate was prepared by means of fine-grained ammonium polyvanadate (APV) produced in vanadium plant. The effects of amount of fine particles, temperature and pH of vanadium solution on preparation of high-density ammonium polyvanadate were investigated. The research results showed that the density of APV could be achieved 0.88g/cm3 under the conditions of addition of 13-31% fine particles, temperature range from 70°C to 100°C and the pH of vanadium solution range from 2.5 to 4, but loss rate of vanadium was the lowest. Moreover, the particle size of high-density ammonium polyvanadate mainly distributes in range of 10 ~ 90μm and is significantly larger than that of the fine APV particles, on the basis of results of the laser particle size analyzer.