With the rapid development of Internet of things and cloud computing,big data and its related science have become the focus of industry and academia.In this paper,we analyzes big data science from the perspective of paradigm theory and expounds the difference and connection between big data and traditional research.Three major challenges brought by big data are proposed in perspective of machine learning,with the corresponding scientific problems following.In addition,this paper introduces several insights of big data science from the perspective of the forth paradigm and its positive significance.In the end,we summarize and look forward to the challenges of big data science in the future.