Background: Day care that is designed for people with dementia aims to increase the users' quality of life (QoL). The objective of the study was to compare the QoL of people with dementia attending day care with those not attending day care. Methods: The study is based on baseline data from a project using a quasi-experimental design, including a group of day care users (n = 183) and a comparison group not receiving day care (n = 78). Quality of Life-Alzheimer's Disease (QoL-AD) was used as the primary outcome, to collect both self-reported and proxy-based information from family carers on the users' QoL. A linear mixed model was used to examine the differences between groups. Results: Attending day care was significantly associated with higher mean scores of self-reported QoL. There was no difference between the groups in proxy-reported QoL. Analyses of the interaction between group belonging and awareness of memory loss revealed that the participants with shallow or no awareness who attended day care had significant higher mean scores of QoL-AD compared to those not attending day care. Conclusions: Higher self-reported QoL was found among people attending day care designed for people with dementia compared to the comparison group. The difference in QoL ratings was found in the group of day care users with shallow or no awareness of their memory loss. Hence, day care designed for people with dementia might have the potential to increase QoL as it is experienced by the users.