The great scientific development and its consequent results in the field of technology in recent times, led some people to go too far in defining the ability of science to answer all man’s basic questions. So, they believed that science would be able be an alternative to religion in presenting a full worldview. This article tries to compare between the worldview coming out of science and the one that religion leads to, in order to provide a deeper picture of the issue of the relationship between science and religion; for the worldview coming out of science suffers from epistemological problems that refute its sufficiency to play the role of the main source that could meet man’s cognitive needs and draw to him the outlines of his life. It is an incomplete view that does not care about all man’s basic aspects, and it is not safe enough to conform with reality. As for religion, according to a systematic religious knowledge and being based on the philosophy of man’s existence, it offers a complete, comprehensive and certain worldview that answers all man’s basic questions and covers all aspects of his life. This view also explains some facts in the history of science, such as the scientific renaissance in Europe and the scientific backwardness of Muslims after they had experienced the golden scientific age.