To spread the fun and attractiveness of synthetic biology and iGEM, inspired by the recently popular coloring book Secret Garden, we designed an iGEM coloring book. We simplified several important scientific items into stick figures, including DNA, viruses, bacteriophages, and bacteria, so that people would understand some basic concepts of synthetic biology by painting them. Drawing itself is relaxing and thought-provoking, and in the form of drawing, we presented our work and popularized iGEM. To our delight, the public were in favor of color painting and they praised our activity for providing a good chance to broaden their horizons. Finally, we collected more than 200 painting works. Most surprisingly, kids loved our coloring book very much. With their creative imagination, they developed interests in synthetic biology and would possibly be the next generation iGEMers. In this way, science, art, education and public engagement are perfectly combined together.