This article studies the importance of parental figures' presence and family relationship quality in the construction of subjective child well-being, which is a protective factor for mental health. The BMSLSS (Brief Multidimensional Students' Life Satisfaction Scale) questionnaire was applied to a random sample of 827 boys and girls enrolled in seventh grade, from the regions of Valpara & iacute;so, Concepci & oacute;n and Santiago, Chile. Participants of both genders reported high levels of well-being. The majority of them live in a single home (89.1%), with an average of three caregivers and two family economic providers. We also found positive and significant associations between the presence of parental figures and well-being. Family relationship quality is a variable which also significantly explains well-being levels when children live in a single house. These results suggest that it is necessary to explore intra-family attachment characteristics in order to identify and enhance family settings, as these have a significant effect on children' well-being.