Vakil bathhouse in Shiraz is amongst Zand monuments that have built under direct supervision of Karim Khan Zand. This bathhouse is amongst the most remarkable and splendid monuments of Zand era in its massiveness and architecture techniques and decorative ornaments and designs. Most researches about Vakil bathhouse had focused on the archeological, architectural and restoration program aspects. Therefore, the present article studies decorative ornaments and designs if this historical monument. Questions of this article are as follows: How did these decorative ornaments and designs have formed and where did they have adopted? What is the relation between these decorative images and designs with the culture and beliefs of common people? Moreover, which are the contents that used by artist of this era in this decorative ornaments and designs? This research shows that the origin of the decorative elements of this bathhouse is a composition of Iranian-Islamic elements from the ancient until the Safavid era. In fact, Karim Khan's interest in revival of Iranian past by artists as mythological, epic and religious concepts that had roots in common belief had influenced on the formation and creation of these elements.