This meta-analysis examined the prevalence of depression and burden among informal care-givers of people with dementia (PwD) and compared the prevalence of depression between male and female, and spousal and non-spousal, care-givers. The quality of studies was evaluated and moderator variables explored. A search of six electronic databases (PsycARTICLES, PsycINFO, MEDLINE Complete, SCOPUS, Web of Science and ProQuest) was conducted from the first available date to the 31 October 2017. Inclusion criteria involved observational studies on the prevalence of burden or depression among informal care-givers of PwD. Forty-three studies were examined with a total of 16,911 participants. The adjusted pooled prevalence of depression was 31.24 per cent (95% confidence interval (CI) = 27.70, 35.01) and burden was 49.26 per cent (95% CI = 37.15, 61.46), although heterogeneity among prevalence estimates was high. Depression prevalence estimates differed according to the instrument used and the continent where the study was conducted. The odds of having depression were almost one and a half times higher in female compared to male care-givers. No significant difference was observed between spouses and non-spouses. Most studies had a medium risk of bias. Results suggest a great need within this population for interventions that are effective at reducing burden and depressive symptoms. It therefore appears imperative for dementia services that are not providing such interventions to do so.