The COVID-19 pandemic had several negative impacts on child and adolescent victims of domestic violence, especially on those who lived in the residential foster care system. The main goal of the present study was to understand these negative impacts through the perspectives of professionals in Portuguese residential foster care structures using both individual interviews and an online survey. One hundred and three professionals aged between 22 and 64 years (M = 38.39; SD = 8.34) participated in the online survey (86 females and 17 males). Of those, seven professionals, four females and three males aged between 29 and 49 years (M = 38.43, SD = 7.50), were also interviewed. According to the participants, the conditions imposed by the COVID-19 pandemic contributed adversely not only to the increase in domestic violence against children and adolescents but also to the aggravation of the conditions children and adolescents living in the Portuguese residential foster care system were exposed to, namely concerning family relationships, access to resources and services, and institutional dynamics. The results suggest the necessity to develop standard procedures to cope with pandemic situations in the residential foster care system.