Abstract: In the last decade between 20th and 21st century, life sciences, especially molecular biology have witnessed a dramatic change. As a result, it is generally believed that the 21 century is the century of life science. At the same time, it was realized that the leap forward in life sciences cannot be accomplished by biologists alone. Mathematics, physics, chemistry, mechanics, information science were all needed in this process. In this article, we use a few examples of our works to elaborate the physics role in life science researches.