In most laboratory practices for students in medical schools, a laboratory guidebook is given to the students, in which the procedures are precisely described. The students merely follow the guidebook without thinking deeply, which spoils the students and does not entice them to think creatively. Problem-based learning (PBL) could be one means for the students themselves to actively learn, find problems, and resolve them. Such a learning attitude nurtures medical students with lifelong learning as healthcare professionals. We merged PBL and laboratory practices to promote deep thinking habits and developed an integrated laboratory practice. We gave a case sheet to groups of students from several schools. The students raised hypotheses after vivid discussion, designed experimental protocols, and performed the experiments. If the results did not support or disproved the hypothesis, the students set up another hypothesis followed by experiments, lasting for 4 or 5 consecutive days. These procedures are quite similar to those of professional researchers. The main impact achieved was the fact that the students developed the experimental design by themselves, for the first time in their college lives. All students enjoyed the laboratory practice, which they had never experienced before. This is an antidote to the guidebook-navigated traditional laboratory practice, which disappoints many students. As educators in basic medical sciences stand on the edge in terms of educating the next generation, there is a need to provide a strong foundation for medical students to design and perform scientific experiments. The integrated laboratory practice may provide the solution. (Contains 4 figures.)