This article investigates the relationship between the use of library resources and learning outcomes in a Chilean research-centered university by analyzing data from two consecutives semesters of student records, library borrowing, and access to electronic resources through the library. Results show that the access to electronic resources has a greater impact upon performance than the number of library items borrowed. They also show that an increase in the number of sessions dedicated to accessing electronic resources was accompanied by a decrease in the number of library items borrowed as students progress in their degrees. Further analyses showed that students' behavior is attributed more to the requirements of advanced courses (commonly encountered in later years of their degrees) than to personal preferences. This relationship between student records and library services enlightens the impact of different library resources on student learning and offers evidence to rationalize library investments according to their needs and impacts.