Marketing of ultra-processed products is one of the commercial determinants of health, as it influences food preferences and eating habits. Digital marketing has become one of the most important elements of food companies’ marketing mix. In this context, the objective of the current chapter is to discuss the characteristics of digital food marketing, the available evidence on its effects on eating habits, and its implications on public health. Frequent food marketing has been reported across different digital platforms, most of which intends to promote fast food and ultra-processed products high in nutrients associated with non-communicable diseases, including sweetened beverages, chocolate and confectionary, and savory snacks. Children and adolescents are particularly vulnerable to the persuasive effects of digital food marketing. Although the evidence is still limited in scope, several studies have already associated exposure to digital food marketing with increased consumption of unhealthy foods among children and adolescents. This stresses the need to implement regulatory approaches to protect these vulnerable segments of the population from digital marketing of unhealthy foods and beverages.