Background Textbooks play an important role in engineering education, influencing instructors' pedagogical approaches and providing much of the information students learn. Research has explored students' recollections of the roles that textbooks played in their educational experiences, but how students actually use textbooks remains largely unexplored. Purpose This phenomenological study describes engineering students' textbook use during problem-solving activities. This study directly examined how students employed a textbook in order to generate detailed descriptions of students' behaviors, approaches, and reflections regarding their actual problem-solving experiences. Method Ten senior materials engineering students (8 males and 2 females) were asked to think aloud while solving engineering problems. Follow-up retrospective interviews regarding the think aloud session were conducted to gain in-depth information on students' textbook use during the problem-solving activities. Results Students used the textbook primarily to find information related to problem constraints that were explicitly stated in the problem. Furthermore, textbook example problems exerted a strong influence on students' problem-solving processes. Students also reported limitations of the textbook, contrasting it to the diversity of resources available via the Internet. Conclusions This study provides insight into students' textbook use during engineering problem-solving activities. Students' limited application of the textbook during problem solving suggests that textbooks may not be serving their intended purposes.