Background: After having a stroke, most patients are helped by a caregiver with activities that they cannot perform by themselves. The caregiver presence and actions are an important variable that may affect rehabilitation in many ways. The aim of this review study was to evaluate the impact of caregiver presence (or absence) and identity (spouse, family, or foreign domestic worker) on therapeutic exercise performance, depression symptoms, patient–spouse relations and total functional outcomes of stroke patients. Assessing these effects may help health care professionals and families to prioritise/choose the caregiver for their patient/family member. Methods: A narrative literature review was conducted, focusing on one-direction effects (caregiver on patient effects) on the topics of interest mentioned, in a post-stroke population. PubMed, CINAHL, PEDro, Trip database, and Google Scholar were searched, and included studies of most designs and research qualities. The search strategy had not been specified before commencing the review. Each study was analysed individually with the purpose of synthesising the available evidence to achieve a greater understanding of this topic. Results: A total of 17 relevant papers were included: six randomised controlled trials, six observational studies, two systematic reviews, two survey-based studies, and one case series. Trials were consistent with the positive effect that caregivers have on therapeutic exercise performance. Studies have shown a positive effect of caregivers on the patient's depressive symptoms, but only at the chronic phase after stroke. A spouse caregiver seems to more positively affect the patient–spouse relations in the acute phase of rehabilitation, while foreign domestic workers can improve these relations at more chronic phases. The presence of a caregiver is shown to decrease functional outcomes within institutionalised rehabilitation centres, while it is necessary and positively affects functionality at more chronic phases within community settings. Conclusions: The advantages and disadvantages of employing a caregiver depend in many cases on the rehabilitation phase. The caregiver might be beneficial or harmful to the patient's functional progress, depressive symptoms and marital relationship depending on the rehabilitation phase. More studies are needed to assess the caregiver effects on post-stroke patients' rehabilitation and quality of life.