Obesity, a multicausal global health disorder, requires innovative solutions beyond conventional weight control. Plant-derived prebiotics, like inulin, oligofructose, and resistant dextrin, have appeared as promising dietary interventions. These fibers nourish beneficial gut bacteria, which produce short-chain fatty acids (SCFAs) that regulate appetite, enhance fat combustion, and improve metabolic markers. Clinical trials show that the consumption of 8–21 g/day prebiotics for 8–24 weeks reduces body weight, BMI, waist circumference, inflammation, and insulin resistance. By exploring mechanisms, bioactive molecules, and personalized approaches, this review highlights prebiotics’ potential as natural anti-obesity agents. However, further research is needed to optimize their contribution to public health initiatives for the effective management of obesity.