The advancement in technology and its integration in teaching and learning brought in gradual changes to the delivery of education. With this expansion in information and communication technologies, a movement towards knowledge sharing resulted in the birth of Open Educational Resources (OERs). This study was thus focused on Open Educational Resources (OERs) and Post-Graduate Students Academic Achievement. Three (3) research questions and three (3) hypotheses guided the study. The population for this study was four hundred and seventy-two (472) postgraduate students offering a masters’ degree programme from the Faculty of Education, University of Port Harcourt. A sample of 25 students was picked proportionally across the 6 departments to give a total of 150 samples. The instrument for data collection was a questionnaire structured on a 4-point Likert scale, titled Perception of Graduate Students’ on the use of Open Educational Resources (PGSOERs). It contained three sections measuring several variables such as graduate students’ awareness level, the extent of usage of OERs and challenges they experience with the use of OERs. The face and content validity of the instrument was established, and the test-retest method was used to determine the reliability of the instrument, with a reliability coefficient of 6.0 obtained. Data was collected by the researcher and two research assistants. Mean and standard deviation was used to answer the research questions, while the hypotheses were analyzed using Z-test. Some of the findings revealed that the level of awareness of OERs among postgraduate students and their skill for evaluating web-based information is very low. However, It was recommended that great efforts need to be made by teachers, lecturers and educational institutions to highlight the numerous benefits/ importance of OERs activities on postgraduate students at the postgraduate level. Postgraduate students need to be equipped with the much-needed skills to access, evaluate and utilize web-based (internet) information.