The importance of English for the workplace, in addition to that of general English proficiency, is receiving increasing attention from educators and policy makers in the field of teaching English as a foreign language. In order to prepare college students for their professional development, appropriate English-for-specific-purposes (ESP) materials, including those for engineering majors, are needed for college courses. This study evaluated teaching materials on English for Science and Technology (EST), in hope of making contributions to the growth of EST materials that meet the educational needs of students in Taiwan. The EST materials were designed for college engineering majors. In the present study, it was used with two engineering junior classes in Taiwan for three weeks. After the trial teaching period, a questionnaire and a focus group interview were administered to collect learner perception on the EST materials. While the overall results of the questionnaire have indicated a positive attitude toward the materials, a careful examination of the statistics and further exploration of the interview data have revealed certain areas of the materials to be improved. Suggestions to the revision of the materials are provided at the end of the paper.