Optimal outcomes of the educational assessment of students require that teachers should have adequate knowledge of, strong skills in, and favourable attitudes toward educational measurement. The present study investigated differences between preservice and inservice teachers' knowledge of, perceived skills in, and attitudes toward educational measurement. Participants were 279 preservice teachers and 233 inservice teachers from Oman. Results indicated that inservice teachers had a lower level of knowledge, a higher level of perceived skilfulness, and a more favourable attitude toward educational measurement than preservice teachers. In addition, the results not only testified to the value of preservice measurement training, but also showed the merit of teaching practicum and teaching experience when preparing teachers in educational measurement. Implications for professional preparation in educational measurement as well as recommendations for future research are discussed. (Contains 4 tables.)