Course evaluations are an important tool for measuring instructional quality and student satisfaction. However, these are questioned for potential biases. In this research, the mixed-method approach is used to assess the course evaluation instrument administered at a college in the Sultanate of Oman. The Cronbach’s alpha measured the instrument’s internal consistency while the Pearson correlation coefficient determined the relationship between student grades and evaluation scores. It is confirmed in this research that there is a high level of internal consistency in the instrument, affirming its reliability. However, the potential biases are highlighted based on the correlations between grades and specific evaluation items that may affect the accuracy of feedback on teaching quality. To ensure comprehensive and unbiased assessment, enhancements in the instrument are proposed with emphasis on the need for alignment with established educational theories. Effective and reliable course evaluations require student feedback that are critical for continuous improvement in teaching and learning.