If science is a part of religion, then which religion seems best suited to the interests of modern scientists? This paper argues that no other religion is best suited to scientists than a movement called “Religious Humanism” or, simply, “Humanism.” It argues further that Humanism is not the only religion for scientists, for all religions involve some science, and scientists are as much entitled as others to pursue their preferences in matters of values. But Humanism is a religion erected upon the results of modern science, and thus tends to be the religion best suited to the interests of scientists.