Urinalysis is a routine and cheap laboratory test that provides clinically useful information in patients with acute abdominal conditions, including acute pancreatitis. The aim of the study was to assess the relationships between the results of urinalysis and the course of the disease among 65 patients with acute pancreatitis (34 men and 31 women, mean age 61 ± 19 years) at the early phase of the disease, i.e. during the first 72 hours from the onset of symptoms. Mild acute pancreatitis was diagnosed in 47 patients, moderately severe in 13 and severe in 5. The most prevalent abnormalities were proteinuria (43% of patients), high urinary bilirubin (20%), erythrocytes (18%), glucose (18%) and leukocytes (17%). High urinary protein and low specific gravity were associated with more severe acute disease and with acute kidney injury. The severity of bilirubinuria and proteinuria were positively correlated with urine concentrations of neutrophil gelatinase associated lipocalin (NGAL). Urinalysis should be routinely performed in patients with acute pancreatitis.