This study was conducted to evaluate the effects of subclinical hypocalcemia (SCH) on serum concentrations of acute phase proteins (APP) during the peripartum period of Holstein cows and to correlate this disorder with biochemical parameters, body condition score (BCS), body weight (BW), and milk production. According to total calcium concentrations (Ca_t) before calving, the animals were divided into two groups: normocalcemic (NC; >8.5 mg dL^-1, n = 13) and SCH (≤8.5 mg dL^-1, n = 7). Blood samples were collected in the prepartum and postpartum to determine serum concentrations of glucose, aspartate aminotransferase, phosphorus, Ca_t, non-esterified fatty acids, insulin, and APP: albumin (ALB), haptoglobin (HP), and paraoxonase (PON) were analysed. Prepartum, SCH group showed an increase in HP concentrations and decreased ALB related to NC. Postpartum, SCH group showed a greater decrease in BCS and BW, a reduction in negative acute phase proteins ALB and PON and increased HP, and lower milk production than NC cows. We observed that during the peripartum SCH cows experienced more evident changes in their metabolism, alterations in the synthesis of APP, BCS, BW, and milk production, there by demonstrating the importance of calcium homeostasis for health and production of dairy cows.