The objective of this study was to explore the existence of organizational justice more specifically three kinds of justice, namely distributive, procedural and interactional justice in the assessment of performance appraisal that will affect the job performance among the employees of Sarawak government agencies. Correlation analyses were conducted to examine the associations between the variables. The method of sampling is convenience sampling. The size selected samples was 140 persons that they were determined by Cochran formula. The means of collecting data with two standard questionnaire: organizational justice with 17 items and job performance with 10 items. the face and context validity of questionnaire were reviewed by the experts and for measuring the reliability of them was used Cronbach-alpha coefficient. To analyzing data, Pearson correlation coefficient is used. Findings show that organizational justice affects performance appraisal and there is a positive relationship between organizational justice and its dimensions (Procedural justice, distributive justice and interactional justice) and job performance.