Introduction: The school is one of the place for shaping the course of human development Fifteen percentages of children aged 5-14 years were reported to have problems in school adjustment. The child who makes a satisfactory initial adjustment to school is more likely to be successful in their future progress than a child who has difficulty adjusting to the school situation. Child centered Play therapy procedures provide children the opportunity to resolve adjustment difficulties. Objectives: To assess the pre-test and post-test level of adjustment difficulties among the primary school children in experimental group and control group. To find out the effectiveness of child centered play therapy on the level of adjustment difficulties among primary school children in experimental group and control group. To compare the pre-test and post level of adjustment difficulties among primary school children in experimental group. To associate the post-test level of adjustment difficulties among primary school children with their selected demographic variables in experimental group and control group. Methods: A quantitative approach and pre experimental research design with two group pre-test and post-test were utilized in this study. A simple random sampling technique was utilized to get 60primary school children studying at viruthunagar district. Results: The pre- test level of adjustment difficulties in experimental group, out of 30 samples, 6(20%) of them had mild adjustment difficulties, 24(80%) of them had moderate adjustment difficulties and none of them had severe adjustment difficulties as well as no adjustment difficulties. the post-test level of adjustment difficulties in experimental group, out of 30 samples 5(16.67%) of them had no adjustment difficulties, 15(50%) of them had mild adjustment difficulties, 10 (33.33%) of them had moderate adjustment difficulties and none of them were in severe adjustment difficulties. standard deviation of 4.99 and the calculated‘t’ value was 38.02. There was no significant association of the post-test level of adjustment difficulties among of primary school children in control group except type of family and occupation of mother with their selected demographic variables. Conclusion: From the findings, it can be concluded that child centerd play therapy was effective in reducing adjustment difficulties among primary school children.