In order to improve Zhundong coal's ash melting point,four kinds of typical Zhundong coal were taken as coal samples.By using three-element phase diagram of SiO₂-CaO-Al₂O₃,the variation of slagging tendency of Zhundong coal was analyzed,and the relationship between chemical composition and ash melting was investigated by using an ash melting point tester.The results show that,based on the ash melting trend in three-element phase diagram,the addition of right amount of oxide additives can improve the ash melting temperature.Experiments show that Shenhua coal with the adddition of 5% of CaO and 5% of Al₂O₃ can significantly improve the ash melting temperature.The effect of SiO₂ on ash fusion temperature has dual character.The study provides theoretical basis for the practical industrial application of Zhundong coal.Considering from the aspects of economy,power plants and industrial boilers,a mixture of quartzsand,limestone,high alumina can be added to better address Zhundong coal issues.