To evaluate the effectiveness of serum levels of resistin and CD14 expression in monocytes, and high-sensitivity C-reactive protein (hsCRP) in early stages of acute pancreatitis and correct prediction of the severity of acute pancreatitis (AP) using scoring systems. The study involved 10 (29.41%) male and 24 (70.59%) female patients (total n=34) followed for AP diagnosis at the Department of General Surgery, Ataturk University Medical School between July 2008 and September 2009. In all the patients, Ranson and APACHE II scores, serum resistin, hsCRP, and monocyte CD14 expression levels were determined. The patients were divided into two groups as mild and severe AP groups. A control group was formed and the intergroup comparisons were made. Values ≥ 3 based on the Ranson scoring scale and values ≥ 8 in APACHE II scoring scale were considered to indicate severe AP. Evaluations were based on the values obtained on the 1st and 7th days for serum resistin and hsCRP levels and monocyte CD 14 expression. In 17 (50%) patients, severe AP was determined. No statistically significant differences were found between the mean serum resistin levels of AP groups, while the difference for the same parameter between the mild and severe AP groups and the control group was statistically significant. In the severe AP group, the mean 1st day and 7th day serum hsCRP levels were statistically significantly higher. The CD14 expression in monocytes was similar in all the groups. Serum hsCRP concentrations and Ranson and APACHE II scores and serum resistin and hsCRP concentrations on the 1st day were positively correlated. Serum hsCRP measurement is effective in determining the severity of acute pancreatitis. Serum resistin measurement may be a useful early marker in determining the inflammatory response in AP. However, CD14 expression in monocytes was not found to be a useful marker in the diagnosis and prediction of the disease severity in AP patients.