In 2006, a working group from the International Electrotechnical Commission (IEC) defined IEC 62304:2006. Thus, the use of IEC 62304 has become fully harmonized in the United States and Europe. The purpose of IEC 62304 is to provide requirements for Healthcare Systems manufacturers with Software to demonstrate their ability to provide Software that consistently meets customer requirements and applicable regulatory requirements. Objective: This chapter aims to present the fundamentals of IEC 62304 with an Agile Software Development Model. Justification and motivation: In 2021, IEC 62304 completes 15 years. Thus, the authors believe that there are already works that report experiences, analyzes and difficulties in its use. These results can be interesting to direct further research and definitions of methods, models, guides or other materials to comply with IEC 62304. Conclusion: This book chapter provided a lecture with fundamentals of IEC 62304, including an Agile Software Development Model.