Antibiotic resistance (ABR) has been identified as a critical threat to global health at the highest policy fora. A leading cause of ABR is the inappropriate use of antibiotics by both patients and healthcare providers. Although countries around the world have committed to developing and implementing national action plans to tackle ABR, there is a considerable gap in evidence about effective behaviour change interventions addressing inappropriate use of antibiotics in low- and middle-income countries (LMICs), where ABR is growing at an alarming rate. We conducted a systematic review to synthesize evidence about the effectiveness and cost-effectiveness of behaviour change interventions to reduce inappropriate use of antibiotics in LMICs. Three databases were searched using a set of predefined search terms and exclusion criteria. The search identified 43 relevant articles. A narrative synthesis of results was conducted using the Behaviour Change Wheel framework to categorize intervention components. The majority of the reviewed studies were set in lower-middle-income or low-income countries located in Sub-Saharan Africa or East Asia and the Pacific. Twenty-four articles evaluated multi-faceted interventions over a period of 12 months or less. Despite the widespread use of antibiotics in the community, interventions were primarily implemented in public health facilities, targeting health professionals such as doctors, nurses, and other allied medical staff. Although education for providers was the most widely used strategy for influencing antibiotic use, it was shown to be most effective when used in conjunction with training or other enabling and supportive measures to nudge behaviour. Six articles included an evaluation of costs of interventions and found a reduction in costs in inpatient and outpatient settings, and one article found a training and guidelines implementation-based intervention to be highly cost-effective. However, the small number of articles conducting an economic evaluation highlights the need for such analyses to be conducted more frequently to support priority setting in resource-constrained environments.