Abstract: Abstract The use of a fully automatic melting furnace for sample preparation resulted in issues such as unstable dilution ratio, long automatic proportioning time, and the presence of bubbles on the surface of the melted sample. The influencing factors of fully automatic melting furnace sample preparation were studied and the optimal parameters for sample preparation were analyzed. The results show that added a baffle next to the balance sensor, the parameters of using a flux particle size of 0.150-0.200 mm, a mass fraction of 25% for the upper layer of the sample fluxing agent, a mass fraction of 75% for the lower layer of the sample fluxing agent, and a maximum melting temperature of 1 085 ℃ to prepare the sample could meet the precision requirements of X-ray fluorescence analysis of the sample.