Historically, over the years, it seems that globally, societies have undergone severe changes, due to population movements, because of wars, internal conflicts and pandemics. History repeats itself today, as wars, civil violence, poverty and pandemics have not stopped, causing an influx of refugees and migrants in the western world (USA, Canada, Germany, Spain, Italy, France, etc.). Greece is one of these countries, which is an accessible place for refugees and migrants, due to its geophysical location. Therefore, up to this day, the coexistence of people with different races, cultures, religions and languages is a point of discussion for the host countries. As a standard value, social justice creates conditions of equality and acceptance of diversity, passing down from generation to generation through family and, later, school. Social justice in education is linked to the ability to perceive conditions that marginalize and exclude children of certain social groups from access to education and knowledge. At the same time, it is linked to the creation of an open democratic school, which promotes the values of equality, acceptance and love for those students, who belong to marginalized social groups, such as refugees and migrants. School leadership of social justice is the continuation of education of social justice, called upon to envision and create this open democratic school through transformational leadership practices. This research comes to add another stone to the previous relevant research, inspired by them, aiming at highlighting the implementation of school leadership of social justice in Greek multicultural primary schools in the light of the views of their principals. Through the development of the theoretical framework, this research paper, presenting historical backgrounds from the Middle Ages to the present day, thoroughly describes the multicultural social context in Greece and Europe, as well as social justice in the educational and school leadership process. Specifically, this research study attempts to discover the inclusive practices of school leadership of social justice, which are related to the co-education of refugee/migrant students in the Greek primary schools and to highlight problems that may, possibly, stop them. Action research has been chosen as an appropriate methodological tool, since its main goal is to explore and understand societies and educational systems, as well as to achieve their change to a better quality. The research process, which, in fact, took place in the year 2021, is characterized by a substantial social phenomenon, which stroke humanity, worldwide, at that time. The COVID-19 pandemic brought significant changes to the operation of schools, as education was carried out remotely, through special platforms, resulting in the closure of schools for long periods of time. For this reason, quantitative methods and practices have been used, such as the questionnaire, which is the most appropriate and reliable form of research tool, especially when research takes place in such difficult social conditions. The investigation focused on: a) the search for practices followed by school social justice leaders to include refugee/migrant students, b) the search for problems that may deter these practices, and c) the intercultural values that govern the school leader of social justice. The most important findings of the research can be summarized as follows: a) school leaders believe in the value of social justice and try to implement and promote it, creating an appropriate school environment, b) they believe in the co-education of refugee/migrant children with other students in the same classroom and not at separate times in the school timetable, c) they consider that coexistence with refugee/migrant students is beneficial for all children, d) they believe that the main problem that makes it difficult for them to include refugee/migrant students into the school environment is the different language and religion and e) even if they believe that inclusive practices should be applied for these students, Greek school leaders do not seem to organize and implement intercultural innovative educational programs and events at their schools. The originality and contribution of this research study to the science of school leadership of social justice is essential, as it has given its intercultural dimension in the light of the inclusion of refugee/migrant students. There are not many research studies that focus on the intercultural character of school leadership of social justice. Therefore, this research, in Greece, provides the opportunity to obtain important information for being used by the Greek and international Ministries of Education. The main proposal of this research concerns the design and imperative implementation of Intercultural Education Training Programs for school leaders, as, nowadays, worldwide, not only in Greece, school has a multicultural nature.