The swelling discourses on organisational citizenship behaviour (OCB) have diffused into areas of management and organisational research. The existing literature encapsulates that trust will mediate the relationship between the three dimensions of organisational justice: procedural justice, distributive justice and interactional justice and OCB. Based on the literature discussions, several hypotheses were proposed and conceptual framework was formulated. A total of 411 teachers had responded and participated in the survey. The collected data were analysed using Smart Partial Least Square software. Vigorous two-stage analytical procedure was adopted. The statistical results indicated that trust significantly mediates the relationship between organisational justice and OCB as well as the dimensions of organisational justice and OCB with various degrees of mediating effects. These findings have provided new insights in the organisational behaviour discipline and shed light on trust's mediation in the relationship of organisational justice and OCB.