HealthRecSys 2020 was the 5th International Workshop on Health Recommender Systems held in conjunction with the 14th ACM Conference on Recommender Systems. This workshop followed the previous workshop in 2019 [4] and focused on the application and potentials of recommender systems on health promotion, health care, and health-related topics. By engaging in the discussion and representation of health domains into recommender systems, this workshop facilitated the cross-domain collaborations and exchange of knowledge and infrastructure. This year, in particular, COVID-19-related contributions were discussed.