The goal of this project is to increase the food literacy of people with low socioeconomic status by conveying food knowledge in an enjoyable, indirect, and unforced way. This master thesis proposes a mobile game which enables the target group to receive food literacy and report their diet through gameplay. The game is about dragon raising; it builds a connection between the game world and the real world by encouraging users to feed their dragons with what they buy and eat in real lives. The project started with literature research and a user survey in the supermarket to explore the factors that influenced people’s food choice. The result showed there were mainly two reasons why low SES people were not having healthy food behavior, unwilling to learn food knowledge or report diet: lack of motivation or lack of ability, which is in line with Fogg's Behavior Model. After further research on the characteristics of people with low SES and contextual factors that influence food behavior, the reason became more specific: 1. People didn't have motivation due to the lack of direct feedback about the short-term and long-term benefits of having good food behaviors. 2. People lacked the ability to learn food literacy or report their diet because they were hindered by more pressing matters in their daily life, e.g., financial difficulty, busy lives. Self-Determination Theory and Persuasive Game Design Model were applied together with Fogg's Behavior Model to help with analyzing the user characteristics and contextual factors. After that, the design guideline was made that the design should focus on simplifying the using and learning process (to increase ability) and deliver food knowledge in an attractive and enjoyable way that may relate to their basic needs (to enhance motivation). Before entering the design phase, an analysis of existing food informatics products, including dietary apps and gamified healthcare apps, was conducted to find the typical functional features and most frequently used game elements. Personas and scenarios of two types of user groups were also created based on the research results, leading to the design requirements. During the design phase, creative sessions were carried for idea-generating, followed by two rounds of prototyping test and iterations. Two game concepts with different game elements and design focuses were further developed and tested with users to check to what extent could the concepts meet the design goal and requirements. The final concept was created according to the insights from users' preference and feedback. In the last phase, the design concept was evaluated with experienced designers and dietitian in related fields to get critical feedback and suggestion. The recommendations and limitations were discussed as well in the end.