The oxidation of Al and Ti in the electroslag remelting process causes an uneven axial composition of the electroslag ingot, which adversely affects its performance, including corrosion resistance and mechanical properties. To control the uniformity of Al and Ti content in electroslag ingots, it is necessary to clarify the change in Al and Ti content during the high-temperature electroslag remelting and to reduce the oxidation of Al and Ti in the alloy by optimizing the slag system ratio and smelting conditions. The research status of Al and Ti element control in the electroslag remelting process was reviewed based on the existing literature, taking the low-fluorine slag CaF₂-CaO-Al₂O₃-MgO-TiO₂ and Incoloy 825 alloy as examples. The ion and molecular coexistence theory of slag (IMCT) was used along with FactSage software to summarize the thermodynamic and kinetic research methods. The effects of temperature and components of slag on the equilibrium Al and Ti contents in the alloy were discussed. Based on the film-penetration theory, a kinetics model for predicting Al and Ti contents in the alloy was proposed, and the mathematical equation of the Al and Ti contents vs time in the electroslag process and the slag-metal reaction rate-limiting method were obtained. Results show that the optimum TiO₂ addition during the electroslag remelting for Incoloy 825 alloy is determined to be approximately 10%. The slag-metal equilibrium experimental results were compared and analyzed using IMCT and FactSage. It is found that the FactSage calculation results are more accurate than the IMCT calculation results. The higher the TiO₂ content, the smaller the deviation between the calculated and experimental results.