A classroom assessment environment is a classroom context experienced by students as the teacher determines assessment purposes, develops assessment tasks, defines assessment criteria and standards, provides feedback, and monitors outcomes (Brookhart, 1997). It is usually a group experience varying from class to class dependent upon the teacher's assessment practices (Brookhart, 2004). As such, the measurement of class-level perception of the assessment environment should deserve recognition and investigation. This study aimed at evaluating the measurement of the perceived classroom assessment environment by comparing the psychometric properties of the scale at the student level and class level. Using a multi-stage random sampling process, data were collected from 4088 students nested within 236 classes of the second cycle of the basic education in the Sultanate of Oman. Students responded to the 18-items of Alkharusi's (2011) Perceived Classroom Assessment Environment Scale. Results of the principal axis factoring yielded two factors, learning-oriented and performance-oriented assessment environment, at both levels. However, the two factors explained about 38% of the variance at the class level compared to about 20% of the variance at the student level. Reliability coefficients in terms of Cronbach alpha ranged between 0.79 and 0.83 at the class level compared to 0.65 and 0.67 at the student level.