ABSTRACT Dietary proteins play an essential role in human health, modulating metabolic processes and disease risk through intricate interactions with the gut microbiota. This review focuses on the nutritional heterogeneity of animal‐ and plant‐derived dietary proteins, systematically examining their differential effects on the gut microbiota and host metabolic health, along with the underlying mechanisms. Evidence suggests that, despite limitations such as restricted amino acid profiles and lower digestibility, plant‐derived proteins generally enhance the diversity and functionality of beneficial gut microbiota, thereby promoting metabolic health. In contrast, the effects of animal‐derived proteins are more complex, with health outcomes varying depending on factors such as protein source, processing methods, and intake levels, leading to diverse physiological responses. A key finding is that the enrichment or suppression of gut microbiota and their metabolic products serves as a critical mediator of the health effects associated with dietary proteins. This review underscores the significance of understanding these differences for optimizing gut health and preventing metabolic diseases through dietary interventions. Looking forward, further research is warranted to elucidate the specific mechanisms involved and to explore personalized nutrition strategies, advancing the development of precision health approaches.