As a plant-derived additive, mulberry leaves have been considered a potential feed supplement in livestock production. The present study investigated the metabolic responses in Chinese Erhualian pigs fed a diet with different mulberry leaf powder (MLP) ratios using a metabolomic approach. Three groups of Erhualian pigs were used: N group (normal chow diet), L group (normal chow diet supplemented with 10% MLP) and H group (normal chow diet supplemented with 20% MLP). After 10 weeks, in animals fed 20% MLP diet reduced average backfat thickness (ABF), leaf fat weight and serum triglyceride (TG) levels were noted, and simultaneously the levels of serum lipase of pigs were increased, while in those fed 10% MLP diet ABF and serum TG levels were decreased. In comparison to N group, both L and H groups had lower levels of metabolites such as lactic acid, alanine, galactose, phenylalanine and tyrosine, but higher levels of metabolites mainly including malonic and heptadecanoic acids. Pathway analysis revealed that MLP supplementation might alter multiple metabolic processes mainly involved in galactose metabolism and biosynthesis of amino acids. It was indicated that MLP supplementation in pigs reduces fat deposition and alters multiple nutrient metabolism processes, and improves our understanding of the mechanisms involved in metabolic changes induced by MLP diet.