Background The population is ageing, and psychiatric disorders are common in older people. Those are associated with worsened quality of life. Although the positive relationship between dog ownership and physical health has been documented, data on mental health are scarcer, especially in community‐dwelling older adults. Objective We sought to establish whether owning a dog was associated with a lower number of symptoms of psychological disorders in community‐dwelling older adults. Methods We conducted a systematic review of the literature published between January 2005 and December 2020. We analysed comparative studies of the level of insomnia and symptoms of depression and/or anxiety among community‐dwelling dog owners aged 70 and over. Results The search identified 191 articles, of which 117 full texts were assessed for eligibility. Five cross‐sectional studies and one before‐after with control group study (assessing a total of 25,138 older adults) were included. The mean (range) NOS score (five studies) was 6.8/9 (5–9) and the EPOC score (one study) was 2/8. The association between the presence of a dog and depressive symptoms did not appear to be significant. Regular contact with a dog was associated with fewer symptoms of anxiety. None of the studies specifically examined sleep disorders. Conclusions Although the presence of a dog did not appear to be related to the level of depressive symptoms among community‐dwelling older adults, there might be a beneficial relationship with anxiety. Further investigation is needed ‐ especially with regard to the type of dog and the type of relationship with the dog.