Background: Despite the widespread reliance on mobile clinics for delivering health services in humanitarian emergencies there is little empirical evidence to support their use. We report a narrative systematic review of the empirical evidence evaluating the use of mobile clinics in humanitarian settings. Methods: We searched MEDLINE, EMBASE, Global Health, Health Management Information Consortium, and The Cochrane Library for manuscripts published between 2000 and 2019. We also conducted a grey literature search via Global Health, Open Grey, and the WHO publication database. Empirical studies were included if they reported on at least one of the following evaluation criteria: relevance/appropriateness, connectedness, coherence, coverage, efficiency, effectiveness, and impact.Findings: Five studies met the inclusion criteria: all supported the use of mobile clinics in the particular setting under study. Three studies included controls. Two studies were assessed as good quality. The studies reported on mobile clinics providing non-communicable disease interventions, mental health services, sexual and reproductive health services, and multiple primary health care services in Afghanistan, the Democratic Republic of the Congo , Haiti, and the Occupied Palestinian Territories. Studies assessed one or more of the following evaluation domains: relevance/appropriateness, coverage, efficiency, and effectiveness. Four studies made recommendations including: i) ensure that mobile clinics are designed to complement clinic-based services; ii) improve technological tools to support patient follow-up, improve record-keeping, communication, and coordination; iii) avoid labelling services in a way that might stigmatise attendees; iv) strengthen referral to psychosocial and mental health services; v) partner with local providers to leverage resources; and vi) ensure strong coordination to optimise the continuum of care. Recommendations regarding the evaluation of mobile clinics include carrying out comparative studies of various modalities (including fixed facilities and community health workers) in order to isolate the effects of the mobile clinics. In the absence of a sound evidence base informing the use of mobile clinics in humanitarian crises, we encourage the integration of: i) WASH services, ii) nutrition services, iii) epidemic surveillance, and iv) systems to ensure the quality and safety of patient care. We recommend that future evaluations report against an established evaluation framework. Conclusion: Evidence supporting the use of mobile clinics in humanitarian emergencies is limited. We encourage more studies of the use of mobile clinics in emergency settings.