Abstract Background The purpose of the present study is to develop the Moral Identity Test (MIT) which measures the moral identity of primary school children. Methods The present study was designed as survey research and 516 primary school children were included in the sample. Data were analysed with corrected item-total correlation, exploratory factor analysis (EFA), internal consistency analysis, convergent validity analysis, and item response theory (IRT). Results As a result of the data analysis, it was found that the MIT consists of one construct with ten items and its internal consistency coefficient is .93. Conclusions It was concluded that the MIT can generate reliable and valid results in measuring the moral identity of primary school children whose ages vary between 7 and 11â years.