This research has explored the thematic color preferences and the psychological effect of color within the interior design of healthcare interior spaces, particularly children's hospitals public spaces, in the context of Palestine. The literature indicates that research is needed to identify the colors that provide healing environments for all age ranges of children. The data collection were classified into prime sources and secondary sources. Primary research was carried out in Palestine to enable the collection of data that fits the exact purpose of this research and to increase the reliability of the information. In Palestine, qualitative data were collected during nine co-design and co-creation workshops, including art-based activities and semi-structured interviews. The secondary sources are related to the broad literature review with a focus on empirical studies related to design children’s hospitals. The study uses a thematic analysis approach for analyzing the qualitative data. The key findings of this research identify thematic types of colors that are appropriate for all age ranges of children (i.e., green, blue, yellow, wood, and purple colors). In addition, the findings revealed a strong preference by all stakeholders to include colors connected to nature for the design of children's hospitals in the context of Palestine.