The COVID-19 pandemic has caused detrimental impacts on different population groups throughout the world. This study aimed to explore the impacts of the COVID-19 pandemic’s mandatory lockdown protocols on individual and social activities and mental health conditions of community-dwelling older people in Jakarta, Indonesia. A qualitative design using one-on-one in-depth interviews was employed to collect data from the participants (n = 24) who were recruited using the snowball sampling technique. Data analysis was guided by the five steps proposed in a qualitative data analysis framework, including familiarisation with the data, identification of a thematic framework, indexing the data, charting the data and mapping and interpreting the data. The findings showed that before the COVID-19 outbreak participants engaged in different kinds of regular individual and social activities. However, the COVID-19 outbreak and its mandatory lockdown protocols significantly influenced both their activities and social life, which led to social disconnection and financial difficulties for them. COVID-19 outbreak, mandatory lockdown protocols, and the disruption of individual and social activities of the participants also caused mental health challenges to them, including feelings of loneliness, loss, sadness, stress, and anger. The findings suggest that there is a need for intervention programs addressing the socio-economic and mental health impacts of the COVID-19 pandemic on older populations to help them cope with these challenges. Future studies involving large-scale older populations to comprehensively understand COVID-19 impacts on them are recommended.