This study aims to identify and analyze factors affecting the development of Digital marketing in Vietnamese businesses. Through combining qualitative (in-depth interviews) and quantitative (survey) research methods, the results show that there are six main groups of factors affecting the application and effectiveness of Digital marketing, including: (1) Awareness and knowledge of Digital marketing of business leaders, (2) Human resources and professional skills, (3) Investment budget for Digital marketing, (4) Information technology infrastructure and communications, (5) Market and consumer behavior, and (6) Government policies and regulations. Among them, the factor groups of awareness and knowledge of leaders, human resources and budget are considered to have the strongest impact. Based on these results, the study proposes a number of key solutions to promote sustainable Digital marketing development for Vietnamese businesses such as enhancing awareness and skills training for leaders and employees, the first priority. budget investment, building modern technological infrastructure, and completing the legal framework for support from the Government.