The purpose of this study was to investigate the analytical thinking abilities and attitudes towards science learning of grade-11 students through science, technology, engineering, and mathematics (STEM) education integrated with a problem-based learning in the study of stoichiometry. The research tools consisted of a pre- and post-analytical thinking ability test, a science learning attitude test, classroom observations, student reflective journals, and semi-structured interviews. The findings indicated that STEM learning activities based on problem-based learning successfully developed analytical thinking abilities and attitudes towards science learning. Consequently, the students realized how important theories are, and were able to integrate their knowledge from various fields to solve problems and to create new innovations. About 80% of the students showed higher analytical thinking ability scores above the prescribed criterion of 70% of the full score. After learning, the scores of the students were higher than those before learning at a confidence level of 0.01. The attitudes towards science learning were higher than those before learning at a confidence level of 0.01. The successful activities of STEM started with offering knowledge to students through an inquiry-based process until they could construct the knowledge on their own. After that, the teacher initiated a problem situation and allowed each group of students to create a useful product adopted from the experimental results via integrating STEM knowledge to modify their creative works.