2021 4th International Symposium on Big Data and Applied Statistics（ISBDAS2021) will be held on May 21-23, 2021 in Dali, China. ISBDAS2021 is to bring together innovative academics and industrial experts in the field of Big Data and Applied Statistics to a common forum. The primary goal of the conference is to promote research and developmental activities in Economic Managemen and Informatics and another goal is to promote scientific information interchange between researchers, developers, engineers, students, and practitioners working all around the world. The conference will be held every year to make it an ideal platform for people to share views and experiences in Big Data and Applied Statistics and related areas. We warmly invite you to participate in ISBDAS2021!