The aims of this study were to evaluate metabolic profiles obtained at −14, 14, and 28 days in milk (DIM), and to identify potential predictive biomarkers of Holstein dairy cows with purulent vaginal discharge (PVD) at 28 DIM. The body condition score (BCS) and hematocrit (Hct) were evaluated, and a metabolic profile test (MPT) was performed at −14, 14, and 28 DIM using serum samples. Cows at 28 DIM were classified using a vaginoscopy and divided into groups of healthy cows (n=89) and cows with PVD (n=31). Albumin (Alb), total cholesterol (TCho), calcium (Ca) and, magnesium (Mg) levels were lower in cows with PVD than in healthy cows at 14 DIM. At 28 DIM, levels of Alb, TCho, Ca, blood urea nitrogen (BUN), Mg, and Hct were lower in cows with PVD. A multivariate stepwise logistic regression analysis showed that higher non-esterified fatty acids (NEFA; odds ratios; OR=4.47; P<0.01), lower Alb (OR=0.07; P<0.01) and lower TCho (OR=0.99; P=0.08) at 14 DIM, and lower Hct (OR=0.83; P=0.05), lower Alb (OR=0.12; P<0.01), and lower BUN (OR=0.74; P=0.02) at 28 DIM were significantly associated with PVD. In conclusion, serum Alb levels was a potential indicator associated with PVD, reflecting dietary protein deficiency preceding disease. Our findings suggest that MPT should be considered to monitor health status during the postpartum period for early diagnosis of PVD.