This book constitutes the refereed proceedings of the Second International Conference on Digital Economy, ICDEc 2017, held in Sidi Bou Said, Tunisia, in May 2017.  The 18 papers presented in this volume were carefully reviewed and selected from 46 submissions. The theme of ICDEc 2017 was "Digital Economy: Emerging Technologies and Business Innovation". The conference offered a number of sessions discussing innovative research focusing on emerging technologies which support the digital transformation of business and the economy: digital marketing, digital economy and e-learning, data science and security, and uncertainty in Web data.