During the Qajar era, visual elements such as paintings on Iranian pen cases (qalamdāns) underwent a transformation with the arrival of European painting. Pen-case painting, as one of the common artistic fields in this period, whose images were influenced by worldview, religious thoughts, beliefs, social and political relations and historical background, is one of the important fields for studying and discovering layers of identity found in Qajar art. Why and how the painters of the Qajar era employed the themes of the Christian world on the pen-case images is the main issue of the present research. The objective of the research is to analyze the formal and contextual impacts of the religious painting of the Christian world on the images of Qajar era pen cases. The main question is, "What effect did the European paintings of the Christian world have on the images of pen cases in terms of form and content, and what effect did they have on the visual attitude of pen-case painters of the Qajar era? The findings based on the descriptive-analytical method indicate that the images of the Qajar era pen cases were influenced by the religious painting of the Christian world in terms of form and content. From the form point of view, these effects include four main topics in implying perspective, dimension, applying shading, composition, and space arrangement, and from the point of view of content: joyful tidings, mother and child, sitting Virgin Mary, and saints, which were adopted from European images. Although the Qajar pen-case painter has used European works as models in terms of content, he has not been subject to symbols or narration, as European painters did, and has also used images adopted from the literature and folk tales on the surface of the pen cases in different frames. In some cases, these artists integrated the methods and characteristics of western works that were in line with their tastes into their tradition and created innovative works by combining old and new methods as well as combining western and Iranian painting traditions.