There is a growing appreciation of the significance of socio-cultural context for the experiences of an individual living with dementia. There is, too, an emergent awareness that dementia is a gendered issue, disproportionately affecting women compared with men. However, little attention has been given as yet to the experiences of lesbian and bisexual women living with dementia. This article addresses this gap in knowledge, exploring the significance of the intersection of ageing, gender and sexuality for lesbian and bisexual women with dementia. It suggests that stigma and social marginalisation associated with dementia and with ageing, gender and sexuality intersect to compound the social exclusion of lesbians and bisexual women. This has implications for early diagnosis and treatment. Moreover, community care policy, which is predicated on heterosexist norms fails to take into account older lesbians and bisexual women’s support networks and so is less likely to be attuned to their needs. Residential care provision is perceived by older lesbians and bisexual women as being heteronormative at best and homophobic at worst. Services which do not recognise, validate and support their identities will compound their anxiety, confusion and distress. This may be contrary to Equality and Human Rights legislation and UK social policies. This paper draws upon, and analyses, extracts from a range of authorship, synthesising the material to present novel insights into the significance of gender and sexuality for the experience of dementia and dementia care.