This study aimed at measuring the predictability of the competitive grade in the general diploma by the university cumulative grade of students of A'Sharqiyah University. The study sample consisted of 590 graduated students of A'Sharqiyah University, who are holding the Diploma of General Education for the 2014-2015- 2016 academic years from three colleges: Faculty of Business Administration, Faculty of Applied and Health Sciences, Faculty of Engineering. The results of the study indicated that the competitive grade is predictable at 14.7% of students' university cumulative grade. Its prediction is considered to be average by the size of the effect. The results also indicated that there are no differences in the predictability of the competitive grade between the students who choose pure math (scientific courses) and the students who chose the applied math (art courses). The results also indicated differences in the predictive capacity of the competitive grade attributable to the student's graduated college, and differences between the faculty of engineering and science, which was for the faculty of engineering, and between the faculty of engineering and administration for the faculty of engineering. Regarding the differences in predictive ability according to the school year, the results showed that there were no differences in predictive ability of the competitive grade attributable to the year in which the student graduated. Finally, the results on the predictive ability of secondary school subjects at the university cumulative grade indicated that there was only a statistical indication of pure mathematic subject to predict the university cumulative grade in the Faculty of Engineering, subjects: social studies, Arabic language, biology, and English. For graduates of the Faculty of Science, and subjects: geography, applied mathematics. And English subject for graduates of the Faculty of Management. In the light of these findings, the study concluded with a series of recommendations such as: find standards which have more predictive ability of the university cumulative grade of admission to various university specifications, also design university’s admissions tests which include the achievement aspect, as well as the capabilities and preparations aspect. Keywords: Predictive Ability, Competitive Grade, University Cumulative Grade.