The effect of learning preferences on reading comprehension and motivation/attitude has been researched thoroughly in the field of education as a new approach to learning. However, these three elements have not been studied simultaneously using the Dunn & Dunn's preferred learning style theory. Therefore, this study aims at analyzing the elements that motivate a student to learn and the elements that lead to academic achievement. The study is based on the Dunn & Dunn's preferred learning style theory which emphasizes that each student has a specific learning style and that learner's physical, emotional, and sociological needs must be satisfied within the learning environment. Using an ABAB single case study design, an investigation was conducted to determine how learning style preferences affect reading comprehension achievement and student motivation/attitude in a fourth grade student who is struggling with language processing. To measure his attitude towards learning, The Student's Motivation toward Science Learning scale was adapted, and the Dunn & Dunn learning styles were identified through the Elementary Learning Style Assessment. Results showed that the student's reading comprehension and motivational/attitude levels increased significantly when instruction used the student's preferred learning style. The results of these findings can be utilized by educators and parents to help maximize achievement and motivational/attitude levels in reading comprehension.