The art of mirror work is one of the latest traditional arts which is prevalent in Iran and appeared in garden pavilions and palaces decorations, and then it was used in the decoration of pilgrimage places and sacred shrines. The form, technique and colors used in this art are very diverse and have given special importance to the decorations of sacred shrines. The philosophical-Islamic concept of plurality to unity versus unity to plurality is one of the most important conceptual elements of Islamic philosophy and art that is evident in all branches of Islamic art, including the architecture. The holy shrine of Shahcheragh holiness is one of the blessed places attributed to the son of the Shia imams in Shiraz, whose great importance to the trustees and rulers has made the best decorative elements to be used in this building. In this research, the concept of plurality to unity and symbol of the mirror has been studied in Quranic verses and in terms of mystic’s sight and its importance by later scholars and philosophers has also been enumerated. Also, the mirror work of the sacred shrine of Shahcheragh holiness has been investigated and studied. The research method is based on field observation and photography of the mirror work of the holy shrine of Shahcheragh holiness, information collection by library method and qualitative data analysis. The results of this research revealed that the concept of plurality to unity is hidden in the mirror work of the Shahcheragh’s holiness Holy Shrine.