The current study aimed to investigate the factorial validity of the Occupational Orientation Scale (9_12) for eleventh grader students in the Sultanate of Oman. The study sample included 1721 students from schools in the Governorate of Muscat. Confirmatory factor analysis was conducted using AMOS program on the whole sample. The current study also examined the differential item functioning of the Occupational Orientation Scale according to gender using three different methods (Transformed Item Difficulty, Mantel-Haenszel, Raju UA index). The results of CFA showed a relative decrease in the goodness of fit indices of Holland's six-factor model in the Omani sample. moreover, the results indicated that the DIF was pervasive in the scale. The transformed item difficulty, Mantel-Haenszel procedure, and Raju UA index detected about 15%, 44%, and 63% respectively of items displayed differential item functioning according to gender. The researcher recommended restudying the factorial structure of the scale on other Omani samples and conducting more research to examine the items that exhibited DIF according to gender in the scale.