Coal gasification is a key technology to develop coal based bulk chemicals and clean fuels, and also an important way to achievethe goal of carbon neutrality. High sodium content and its volatilization of Zhundong coal during gasification lead to serious ash-releaseproblems. Therefore, it is of great significance to clarify the ash deposition and slagging mechanism and ash fluidity duringZhundong coal gasification for the clean and efficient utilization of high-sodium coal. Given this, the research progress on the ash chemis⁃try of high-sodium coal during gasification process was reviewed. The forms and content of sodium in coal were summarized. The migrationand transformation mechanisms of sodium in gasification and the ash deposition problem caused by sodium release on the heating surface ofthe gasifier were clarified. The ashing temperature is set at 500 ℃ because the sodium release in high sodium coal is mainly affected bythe gasification temperature. Low melting point sodium-containing minerals are easily generated during the gasification process, reducingthe ash melting temperature of high sodium coal ash. When the content of calcium and iron in high sodium coal is high, the formation oflow-temperature eutectic of anorthite and gehlenite in coal ash at high temperature, and the formation of low melting point spinel by Fe2+reacting with minerals in coal are important reasons for reducing coal ash melting temperature. Meanwhile, the atmosphere has a certain in⁃fluence on the minerals evolution of high-sodium coal during thermal conversion. The melting rate of high-sodium coal is fast,and the av⁃erage melting temperature is low, indicating that the ash has a strong fluidity. The Na2O can provide O2- and break the bridge oxygenbonds, causing the slag to depolymerize and reducing the viscosity value. The slag grid structure depolymerizes, the viscosity is reduced.The melting mechanism confirms the melting-dissolution mechanism. The precipitation of crystals in the slag during cooling has a crucialimpact on the viscosity. The introduction of Na2O reduces the crystallization temperature of slag and changes the crystal type. At the sametime, the viscosity activation energy and crystallization ability of the slag are reduced.